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Binary Search II

Day 1

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Day 2

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Day 3

0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n) 80 89.11

Day 4

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Day 5

0287 Find the Duplicate Number Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Two_Pointers, Bit_Manipulation, Big_O_Time_O(n)_Space_O(n) 257 30.11

Day 6

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Day 7

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Day 8

0240 Search a 2D Matrix II Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer, Big_O_Time_O(n+m)_Space_O(1) 142 60.76

Day 9

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Day 10

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Day 11

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Day 12

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Day 13

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Day 14

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Day 15

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Day 16

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Day 17

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Day 18

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Day 19

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Day 20

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Dynamic Programming I

Day 1

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Day 2

0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) 15 94.90

Day 3

0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 44 99.89

Day 4

0055 Jump Game Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 189 38.02
0045 Jump Game II Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 85 88.80

Day 5

0053 Maximum Subarray Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 270 38.35

Day 6

0152 Maximum Product Subarray Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 71 90.35

Day 7

0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 328 35.43

Day 8

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Day 9

0139 Word Break Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max) 64 98.44
0042 Trapping Rain Water Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(1) 81 89.96

Day 10

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Day 11

0096 Unique Binary Search Trees Medium Top_100_Liked_Questions, Dynamic_Programming, Math, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(1) 13 98.48

Day 12

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Day 13

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Day 14

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Day 15

0062 Unique Paths Medium Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(m*n)_Space_O(m*n) 16 93.42

Day 16

0064 Minimum Path Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(m*n)_Space_O(m*n) 74 94.37
0221 Maximal Square Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(m*n)_Space_O(m*n) 199 36.75

Day 17

0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 61 99.50

Day 18

0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n) 80 89.11

Day 19

1143 Longest Common Subsequence Medium Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n*m)_Space_O(n*m) 59 90.45
0072 Edit Distance Hard Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) 51 95.38

Day 20

0322 Coin Change Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount) 78 90.63

Day 21

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Programming Skills I

Day 1 Basic Data Type

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Day 2 Operator

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Day 3 Conditional Statements

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Day 4 Loop

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Day 5 Function

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Day 6 Array

0283 Move Zeroes Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 133 96.30

Day 7 Array

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Day 8 String

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Day 9 String

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Day 10 Linked List and Tree

0104 Maximum Depth of Binary Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H) 65 93.31

Day 11 Containers and Libraries

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Day 12 Class and Object

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Programming Skills II

Day 1

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Day 2

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Day 3

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Day 4

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Day 5

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Day 6

0739 Daily Temperatures Medium Top_100_Liked_Questions, Array, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(n) 376 44.29

Day 7

0048 Rotate Image Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Big_O_Time_O(n^2)_Space_O(1) 92 97.78

Day 8

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Day 9

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Day 10

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Day 11

0049 Group Anagrams Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n) 145 96.20

Day 12

0438 Find All Anagrams in a String Medium Top_100_Liked_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n+m)_Space_O(1) 103 97.89

Day 13

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Day 14

0138 Copy List with Random Pointer Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Big_O_Time_O(N)_Space_O(N) 59 96.51

Day 15

0002 Add Two Numbers Medium Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Big_O_Time_O(max(N,M))_Space_O(max(N,M)) 84 77.30

Day 16

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Day 17

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Day 18

0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N) 105 95.77

Day 19

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Day 20

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Graph Theory I

0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(M*N)_Space_O(M*N) 119 51.45

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Day 7 Standard Traversal

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Day 8 Standard Traversal

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Day 9 Standard Traversal

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Day 10 Standard Traversal

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Day 13 Graph Theory

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Day 14 Graph Theory

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SQL I

Day 1 Select

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Day 2 Select and Order

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Day 3 String Processing Functions

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Day 4 Union and Select

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Day 5 Union

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Day 6 Union

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Day 7 Function

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Day 8 Function

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Day 9 Control of Flow

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Day 10 Where

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Level 1

Day 1 Prefix Sum

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Day 2 String

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Day 3 Linked List

0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) 69 92.74
0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) 57 95.02

Day 4 Linked List

0142 Linked List Cycle II Medium Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 72 94.58

Day 5 Greedy

0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 328 35.43

Day 6 Tree

0102 Binary Tree Level Order Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) 97 98.14

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Day 8 Binary Search Tree

0098 Validate Binary Search Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N)) 75 97.31

Day 9 Graph/BFS/DFS

0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(M*N)_Space_O(M*N) 119 51.45

Day 10 Dynamic Programming

0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) 15 94.90

Day 11 Dynamic Programming

0062 Unique Paths Medium Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(m*n)_Space_O(m*n) 16 93.42

Day 12 Sliding Window/Two Pointer

0438 Find All Anagrams in a String Medium Top_100_Liked_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n+m)_Space_O(1) 103 97.89

Day 13 Hashmap

0001 Two Sum Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) 134 81.26

Day 14 Stack

0394 Decode String Medium Top_100_Liked_Questions, String, Stack, Recursion, Big_O_Time_O(n)_Space_O(n) 44 99.55

Day 15 Heap

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Level 2

Day 1 Implementation/Simulation

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Day 2 String

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Day 3 Linked List

0019 Remove Nth Node From End of List Medium Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Big_O_Time_O(L)_Space_O(L) 69 90.79
0234 Palindrome Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Stack, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) 306 31.81

Day 4 Linked List

0148 Sort List Medium Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Big_O_Time_O(log(N))_Space_O(log(N)) 141 45.08

Day 5 Greedy

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Day 6 Tree

0226 Invert Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 58 94.38

Day 7 Tree

0543 Diameter of Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 74 84.67
0437 Path Sum III Medium Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 76 97.16
0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 76 90.98
0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 63 96.89

Day 9 Binary Search Tree

0230 Kth Smallest Element in a BST Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n) 69 98.79

Day 10 Graph/BFS/DFS

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Day 11 Graph/BFS/DFS

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Day 12 Dynamic Programming

0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 44 99.89
0322 Coin Change Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount) 78 90.63

Day 13 Dynamic Programming

0416 Partition Equal Subset Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Big_O_Time_O(n*sums)_Space_O(n*sums) 95 97.38
0152 Maximum Product Subarray Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 71 90.35

Day 14 Sliding Window/Two Pointer

0003 Longest Substring Without Repeating Characters Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1) 50 98.40
0076 Minimum Window Substring Hard Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(s.length())_Space_O(1) 56 98.72

Day 15 Tree

0101 Symmetric Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(log(N)) 64 97.79

Day 16 Design

0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N) 105 95.77
0208 Implement Trie (Prefix Tree) Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N) 178 88.12

Day 17 Interval

0056 Merge Intervals Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n) 149 89.48

Day 18 Stack

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Day 19 Union Find

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Day 20 Brute Force/Backtracking

0039 Combination Sum Medium Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n) 94 99.60
0046 Permutations Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!) 96 96.56

Udemy

Udemy Integers

0136 Single Number Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) 87 93.37
0007 Reverse Integer Medium Top_Interview_Questions, Math 23 59.02
0009 Palindrome Number Easy Math 42 34.61

Udemy Strings

0003 Longest Substring Without Repeating Characters Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1) 50 98.40
0020 Valid Parentheses Easy Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Big_O_Time_O(n)_Space_O(n) 53 96.68
0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 61 99.50
0394 Decode String Medium Top_100_Liked_Questions, String, Stack, Recursion, Big_O_Time_O(n)_Space_O(n) 44 99.55
0049 Group Anagrams Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n) 145 96.20
0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 63 96.89
0153 Find Minimum in Rotated Sorted Array Medium Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N) 64 88.59

Udemy Arrays

0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 328 35.43
0283 Move Zeroes Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 133 96.30
0001 Two Sum Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) 134 81.26
0189 Rotate Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 143 94.32
0055 Jump Game Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 189 38.02
0075 Sort Colors Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 98 93.59
0238 Product of Array Except Self Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Prefix_Sum, Big_O_Time_O(n^2)_Space_O(n) 141 94.24
0041 First Missing Positive Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) 178 36.64
0239 Sliding Window Maximum Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Heap_Priority_Queue, Sliding_Window, Queue, Monotonic_Queue, Big_O_Time_O(n*k)_Space_O(n+k) 493 46.05

Udemy Two Pointers

0042 Trapping Rain Water Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(1) 81 89.96
0015 3Sum Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2) 173 75.85

Udemy Famous Algorithm

0053 Maximum Subarray Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 270 38.35
0169 Majority Element Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 98 66.71

Udemy Sorting Algorithms

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Udemy 2D Arrays/Matrix

0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 76 90.98
0048 Rotate Image Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Big_O_Time_O(n^2)_Space_O(1) 92 97.78
0073 Set Matrix Zeroes Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Matrix, Big_O_Time_O(m*n)_Space_O(1) 124 96.92
0056 Merge Intervals Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n) 149 89.48

Udemy Linked List

0114 Flatten Binary Tree to Linked List Medium Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Big_O_Time_O(N)_Space_O(N) 52 98.71
0024 Swap Nodes in Pairs Medium Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) 58 98.51
0142 Linked List Cycle II Medium Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 72 94.58
0141 Linked List Cycle Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 76 99.02
0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) 57 95.02
0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) 69 92.74
0160 Intersection of Two Linked Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(M+N)_Space_O(1) 118 53.65
0234 Palindrome Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Stack, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) 306 31.81
0138 Copy List with Random Pointer Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Big_O_Time_O(N)_Space_O(N) 59 96.51
0025 Reverse Nodes in k-Group Hard Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(k) 75 86.97
0146 LRU Cache Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Design, Linked_List, Doubly_Linked_List, Big_O_Time_O(1)_Space_O(capacity) 780 34.57

Udemy Tree Stack Queue

0094 Binary Tree Inorder Traversal Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Big_O_Time_O(n)_Space_O(n) 90 99.30
0102 Binary Tree Level Order Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) 97 98.14
0543 Diameter of Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 74 84.67
0226 Invert Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 58 94.38
0104 Maximum Depth of Binary Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H) 65 93.31
0124 Binary Tree Maximum Path Sum Hard Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) 85 91.69
0098 Validate Binary Search Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N)) 75 97.31
0236 Lowest Common Ancestor of a Binary Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 76 98.04

Udemy Trie and Heap

0208 Implement Trie (Prefix Tree) Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N) 178 88.12

Udemy Graph

0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(M*N)_Space_O(M*N) 119 51.45

Udemy Dynamic Programming

0139 Word Break Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max) 64 98.44
0152 Maximum Product Subarray Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 71 90.35
0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 44 99.89
0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) 15 94.90
0064 Minimum Path Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(m*n)_Space_O(m*n) 74 94.37
0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n) 80 89.11
1143 Longest Common Subsequence Medium Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n*m)_Space_O(n*m) 59 90.45
0072 Edit Distance Hard Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) 51 95.38
0010 Regular Expression Matching Hard Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Recursion, Big_O_Time_O(m*n)_Space_O(m*n) 59 96.10

Udemy Backtracking/Recursion

0022 Generate Parentheses Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(2^n)_Space_O(n) 81 99.57
0039 Combination Sum Medium Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n) 94 99.60
0078 Subsets Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Big_O_Time_O(2^n)_Space_O(n*2^n) 101 94.29
0017 Letter Combinations of a Phone Number Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Big_O_Time_O(4^n)_Space_O(n) 108 95.24
0046 Permutations Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!) 96 96.56

Udemy Bit Manipulation

0338 Counting Bits Easy Top_100_Liked_Questions, Dynamic_Programming, Bit_Manipulation, Big_O_Time_O(num)_Space_O(num) 67 98.82

Udemy Design

0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N) 105 95.77

Data Structure I

Day 1 Array

0053 Maximum Subarray Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 270 38.35

Day 2 Array

0001 Two Sum Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) 134 81.26

Day 3 Array

0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 328 35.43

Day 4 Array

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Day 5 Array

0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 76 90.98

Day 6 String

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Day 7 Linked List

0141 Linked List Cycle Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 76 99.02
0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) 69 92.74

Day 8 Linked List

0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) 57 95.02

Day 9 Stack Queue

0020 Valid Parentheses Easy Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Big_O_Time_O(n)_Space_O(n) 53 96.68

Day 10 Tree

0094 Binary Tree Inorder Traversal Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Big_O_Time_O(n)_Space_O(n) 90 99.30

Day 11 Tree

0102 Binary Tree Level Order Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) 97 98.14
0104 Maximum Depth of Binary Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H) 65 93.31
0101 Symmetric Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(log(N)) 64 97.79

Day 12 Tree

0226 Invert Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 58 94.38

Day 13 Tree

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Day 14 Tree

0098 Validate Binary Search Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N)) 75 97.31

Data Structure II

Day 1 Array

0136 Single Number Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) 87 93.37
0169 Majority Element Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 98 66.71
0015 3Sum Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2) 173 75.85

Day 2 Array

0075 Sort Colors Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 98 93.59
0056 Merge Intervals Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n) 149 89.48

Day 3 Array

0048 Rotate Image Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Big_O_Time_O(n^2)_Space_O(1) 92 97.78

Day 4 Array

0240 Search a 2D Matrix II Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer, Big_O_Time_O(n+m)_Space_O(1) 142 60.76

Day 5 Array

0238 Product of Array Except Self Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Prefix_Sum, Big_O_Time_O(n^2)_Space_O(n) 141 94.24
0560 Subarray Sum Equals K Medium Top_100_Liked_Questions, Array, Hash_Table, Prefix_Sum, Big_O_Time_O(n)_Space_O(n) 135 46.56

Day 6 String

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Day 7 String

0763 Partition Labels Medium Top_100_Liked_Questions, String, Hash_Table, Greedy, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 82 98.72

Day 8 String

0049 Group Anagrams Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n) 145 96.20

Day 9 String

0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 61 99.50

Day 10 Linked List

0002 Add Two Numbers Medium Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Big_O_Time_O(max(N,M))_Space_O(max(N,M)) 84 77.30
0142 Linked List Cycle II Medium Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 72 94.58

Day 11 Linked List

0160 Intersection of Two Linked Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(M+N)_Space_O(1) 118 53.65

Day 12 Linked List

0024 Swap Nodes in Pairs Medium Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) 58 98.51

Day 13 Linked List

0025 Reverse Nodes in k-Group Hard Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(k) 75 86.97

Day 14 Stack Queue

0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N) 105 95.77

Day 15 Tree

0105 Construct Binary Tree from Preorder and Inorder Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Big_O_Time_O(N)_Space_O(N) 53 99.83

Day 16 Tree

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Day 17 Tree

0230 Kth Smallest Element in a BST Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n) 69 98.79

Day 18 Tree

0236 Lowest Common Ancestor of a Binary Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 76 98.04

Day 19 Graph

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Day 20 Heap Priority Queue

0215 Kth Largest Element in an Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Heap_Priority_Queue, Divide_and_Conquer, Quickselect, Big_O_Time_O(n*log(n))_Space_O(log(n)) 252 46.14
0347 Top K Frequent Elements Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Heap_Priority_Queue, Counting, Divide_and_Conquer, Quickselect, Bucket_Sort, Big_O_Time_O(n*log(n))_Space_O(k) 125 95.29

Day 21 Heap Priority Queue

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Algorithm I

0035 Search Insert Position Easy Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 64 95.18

Day 2 Two Pointers

0189 Rotate Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 143 94.32

Day 3 Two Pointers

0283 Move Zeroes Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 133 96.30

Day 4 Two Pointers

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Day 5 Two Pointers

0019 Remove Nth Node From End of List Medium Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Big_O_Time_O(L)_Space_O(L) 69 90.79

Day 6 Sliding Window

0003 Longest Substring Without Repeating Characters Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1) 50 98.40

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Day 10 Recursion Backtracking

0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) 69 92.74
0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) 57 95.02

Day 11 Recursion Backtracking

0046 Permutations Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!) 96 96.56

Day 12 Dynamic Programming

0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) 15 94.90
0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 44 99.89

Day 13 Bit Manipulation

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Day 14 Bit Manipulation

0136 Single Number Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) 87 93.37

Algorithm II

Day 1 Binary Search

0034 Find First and Last Position of Element in Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 120 81.66
0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 63 96.89
0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 76 90.98
0153 Find Minimum in Rotated Sorted Array Medium Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N) 64 88.59

Day 3 Two Pointers

0015 3Sum Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2) 173 75.85

Day 4 Two Pointers

0011 Container With Most Water Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Greedy, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 251 30.70

Day 5 Sliding Window

0438 Find All Anagrams in a String Medium Top_100_Liked_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n+m)_Space_O(1) 103 97.89
0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(M*N)_Space_O(M*N) 119 51.45

Day 7 Breadth First Search Depth First Search

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Day 8 Breadth First Search Depth First Search

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Day 9 Recursion Backtracking

0078 Subsets Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Big_O_Time_O(2^n)_Space_O(n*2^n) 101 94.29

Day 10 Recursion Backtracking

0039 Combination Sum Medium Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n) 94 99.60

Day 11 Recursion Backtracking

0017 Letter Combinations of a Phone Number Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Big_O_Time_O(4^n)_Space_O(n) 108 95.24
0022 Generate Parentheses Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(2^n)_Space_O(n) 81 99.57
0079 Word Search Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Backtracking, Big_O_Time_O(4^(m*n))_Space_O(m*n) 152 99.69

Day 12 Dynamic Programming

0055 Jump Game Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 189 38.02

Day 13 Dynamic Programming

0045 Jump Game II Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 85 88.80
0062 Unique Paths Medium Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(m*n)_Space_O(m*n) 16 93.42

Day 14 Dynamic Programming

0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 61 99.50

Day 15 Dynamic Programming

0139 Word Break Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max) 64 98.44

Day 16 Dynamic Programming

0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n) 80 89.11

Day 17 Dynamic Programming

1143 Longest Common Subsequence Medium Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n*m)_Space_O(n*m) 59 90.45

Day 18 Dynamic Programming

0072 Edit Distance Hard Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) 51 95.38
0322 Coin Change Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount) 78 90.63

Day 19 Bit Manipulation

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Day 20 Others

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Day 21 Others

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Binary Search I

Day 1

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Day 2

0035 Search Insert Position Easy Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 64 95.18

Day 3

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Day 4

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Day 5

0034 Find First and Last Position of Element in Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 120 81.66

Day 6

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Day 7

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Day 8

0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 76 90.98

Day 9

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Day 10

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Day 11

0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 63 96.89

Day 12

0153 Find Minimum in Rotated Sorted Array Medium Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N) 64 88.59

Algorithms

# Title Difficulty Tag Time, ms Time, %
1143 Longest Common Subsequence Medium Top_100_Liked_Questions, String, Dynamic_Programming, Algorithm_II_Day_17_Dynamic_Programming, Dynamic_Programming_I_Day_19, Udemy_Dynamic_Programming, Big_O_Time_O(n*m)_Space_O(n*m) 59 90.45
0763 Partition Labels Medium Top_100_Liked_Questions, String, Hash_Table, Greedy, Two_Pointers, Data_Structure_II_Day_7_String, Big_O_Time_O(n)_Space_O(1) 82 98.72
0739 Daily Temperatures Medium Top_100_Liked_Questions, Array, Stack, Monotonic_Stack, Programming_Skills_II_Day_6, Big_O_Time_O(n)_Space_O(n) 376 44.29
0647 Palindromic Substrings Medium Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n) 48 92.55
0560 Subarray Sum Equals K Medium Top_100_Liked_Questions, Array, Hash_Table, Prefix_Sum, Data_Structure_II_Day_5_Array, Big_O_Time_O(n)_Space_O(n) 135 46.56
0543 Diameter of Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Level_2_Day_7_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) 74 84.67
0494 Target Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Backtracking, Big_O_Time_O(n*(sum+s))_Space_O(n*(sum+s)) 62 99.32
0438 Find All Anagrams in a String Medium Top_100_Liked_Questions, String, Hash_Table, Sliding_Window, Algorithm_II_Day_5_Sliding_Window, Programming_Skills_II_Day_12, Level_1_Day_12_Sliding_Window/Two_Pointer, Big_O_Time_O(n+m)_Space_O(1) 103 97.89
0437 Path Sum III Medium Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Level_2_Day_7_Tree, Big_O_Time_O(n)_Space_O(n) 76 97.16
0416 Partition Equal Subset Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Level_2_Day_13_Dynamic_Programming, Big_O_Time_O(n*sums)_Space_O(n*sums) 95 97.38
0394 Decode String Medium Top_100_Liked_Questions, String, Stack, Recursion, Level_1_Day_14_Stack, Udemy_Strings, Big_O_Time_O(n)_Space_O(n) 44 99.55
0347 Top K Frequent Elements Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Heap_Priority_Queue, Counting, Divide_and_Conquer, Quickselect, Bucket_Sort, Data_Structure_II_Day_20_Heap_Priority_Queue, Big_O_Time_O(n*log(n))_Space_O(k) 125 95.29
0338 Counting Bits Easy Top_100_Liked_Questions, Dynamic_Programming, Bit_Manipulation, Udemy_Bit_Manipulation, Big_O_Time_O(num)_Space_O(num) 67 98.82
0322 Coin Change Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_20, Level_2_Day_12_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(amount) 78 90.63
0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Algorithm_II_Day_16_Dynamic_Programming, Binary_Search_II_Day_3, Dynamic_Programming_I_Day_18, Udemy_Dynamic_Programming, Big_O_Time_O(n*log_n)_Space_O(n) 80 89.11
0295 Find Median from Data Stream Hard Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Design, Heap_Priority_Queue, Data_Stream, Big_O_Time_O(n*log_n)_Space_O(n) 658 24.88
0287 Find the Duplicate Number Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Two_Pointers, Bit_Manipulation, Binary_Search_II_Day_5, Big_O_Time_O(n)_Space_O(n) 257 30.11
0283 Move Zeroes Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Algorithm_I_Day_3_Two_Pointers, Programming_Skills_I_Day_6_Array, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) 133 96.30
0240 Search a 2D Matrix II Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer, Data_Structure_II_Day_4_Array, Binary_Search_II_Day_8, Big_O_Time_O(n+m)_Space_O(1) 142 60.76
0239 Sliding Window Maximum Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Heap_Priority_Queue, Sliding_Window, Queue, Monotonic_Queue, Udemy_Arrays, Big_O_Time_O(n*k)_Space_O(n+k) 493 46.05
0238 Product of Array Except Self Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Prefix_Sum, Data_Structure_II_Day_5_Array, Udemy_Arrays, Big_O_Time_O(n^2)_Space_O(n) 141 94.24
0236 Lowest Common Ancestor of a Binary Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Data_Structure_II_Day_18_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) 76 98.04
0234 Palindrome Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Stack, Linked_List, Recursion, Level_2_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(1) 306 31.81
0230 Kth Smallest Element in a BST Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Data_Structure_II_Day_17_Tree, Level_2_Day_9_Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n) 69 98.79
0226 Invert Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_12_Tree, Level_2_Day_6_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) 58 94.38
0221 Maximal Square Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Dynamic_Programming_I_Day_16, Big_O_Time_O(m*n)_Space_O(m*n) 199 36.75
0215 Kth Largest Element in an Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Heap_Priority_Queue, Divide_and_Conquer, Quickselect, Data_Structure_II_Day_20_Heap_Priority_Queue, Big_O_Time_O(n*log(n))_Space_O(log(n)) 252 46.14
0208 Implement Trie (Prefix Tree) Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Level_2_Day_16_Design, Udemy_Trie_and_Heap, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N) 178 88.12
0207 Course Schedule Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Graph, Topological_Sort, Big_O_Time_O(N)_Space_O(N) 95 91.94
0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Data_Structure_I_Day_8_Linked_List, Algorithm_I_Day_10_Recursion_Backtracking, Level_1_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) 57 95.02
0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Algorithm_II_Day_6_Breadth_First_Search_Depth_First_Search, Graph_Theory_I_Day_1_Matrix_Related_Problems, Level_1_Day_9_Graph/BFS/DFS, Udemy_Graph, Big_O_Time_O(M*N)_Space_O(M*N) 119 51.45
0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Algorithm_I_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_3, Level_2_Day_12_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 44 99.89
0189 Rotate Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Two_Pointers, Algorithm_I_Day_2_Two_Pointers, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) 143 94.32
0169 Majority Element Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Data_Structure_II_Day_1_Array, Udemy_Famous_Algorithm, Big_O_Time_O(n)_Space_O(1) 98 66.71
0160 Intersection of Two Linked Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Data_Structure_II_Day_11_Linked_List, Udemy_Linked_List, Big_O_Time_O(M+N)_Space_O(1) 118 53.65
0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Data_Structure_II_Day_14_Stack_Queue, Programming_Skills_II_Day_18, Level_2_Day_16_Design, Udemy_Design, Big_O_Time_O(1)_Space_O(N) 105 95.77
0153 Find Minimum in Rotated Sorted Array Medium Top_100_Liked_Questions, Array, Binary_Search, Algorithm_II_Day_2_Binary_Search, Binary_Search_I_Day_12, Udemy_Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N) 64 88.59
0152 Maximum Product Subarray Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Dynamic_Programming_I_Day_6, Level_2_Day_13_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 71 90.35
0148 Sort List Medium Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Level_2_Day_4_Linked_List, Big_O_Time_O(log(N))_Space_O(log(N)) 141 45.08
0146 LRU Cache Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Design, Linked_List, Doubly_Linked_List, Udemy_Linked_List, Big_O_Time_O(1)_Space_O(capacity) 780 34.57
0142 Linked List Cycle II Medium Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Data_Structure_II_Day_10_Linked_List, Level_1_Day_4_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) 72 94.58
0141 Linked List Cycle Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Data_Structure_I_Day_7_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) 76 99.02
0139 Word Break Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Algorithm_II_Day_15_Dynamic_Programming, Dynamic_Programming_I_Day_9, Udemy_Dynamic_Programming, Big_O_Time_O(M+max*N)_Space_O(M+N+max) 64 98.44
0138 Copy List with Random Pointer Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Programming_Skills_II_Day_14, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(N) 59 96.51
0136 Single Number Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Data_Structure_II_Day_1_Array, Algorithm_I_Day_14_Bit_Manipulation, Udemy_Integers, Big_O_Time_O(N)_Space_O(1) 87 93.37
0131 Palindrome Partitioning Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(N*2^N)_Space_O(2^N*N) 677 38.30
0128 Longest Consecutive Sequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Union_Find, Big_O_Time_O(N_log_N)_Space_O(1) 201 61.50
0124 Binary Tree Maximum Path Sum Hard Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(N) 85 91.69
0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Data_Structure_I_Day_3_Array, Dynamic_Programming_I_Day_7, Level_1_Day_5_Greedy, Udemy_Arrays, Big_O_Time_O(N)_Space_O(1) 328 35.43
0114 Flatten Binary Tree to Linked List Medium Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(N) 52 98.71
0105 Construct Binary Tree from Preorder and Inorder Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Data_Structure_II_Day_15_Tree, Big_O_Time_O(N)_Space_O(N) 53 99.83
0104 Maximum Depth of Binary Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Programming_Skills_I_Day_10_Linked_List_and_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(H) 65 93.31
0102 Binary Tree Level Order Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Level_1_Day_6_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(N) 97 98.14
0101 Symmetric Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Level_2_Day_15_Tree, Big_O_Time_O(N)_Space_O(log(N)) 64 97.79
0098 Validate Binary Search Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Data_Structure_I_Day_14_Tree, Level_1_Day_8_Binary_Search_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(log(N)) 75 97.31
0096 Unique Binary Search Trees Medium Top_100_Liked_Questions, Dynamic_Programming, Math, Tree, Binary_Tree, Binary_Search_Tree, Dynamic_Programming_I_Day_11, Big_O_Time_O(n)_Space_O(1) 13 98.48
0094 Binary Tree Inorder Traversal Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Data_Structure_I_Day_10_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) 90 99.30
0084 Largest Rectangle in Histogram Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Stack, Monotonic_Stack, Big_O_Time_O(n_log_n)_Space_O(log_n) 304 30.92
0079 Word Search Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Big_O_Time_O(4^(m*n))_Space_O(m*n) 152 99.69
0078 Subsets Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Algorithm_II_Day_9_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n*2^n) 101 94.29
0076 Minimum Window Substring Hard Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Level_2_Day_14_Sliding_Window/Two_Pointer, Big_O_Time_O(s.length())_Space_O(1) 56 98.72
0075 Sort Colors Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Data_Structure_II_Day_2_Array, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) 98 93.59
0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Data_Structure_I_Day_5_Array, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_8, Level_2_Day_8_Binary_Search, Udemy_2D_Arrays/Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 76 90.98
0073 Set Matrix Zeroes Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Matrix, Udemy_2D_Arrays/Matrix, Big_O_Time_O(m*n)_Space_O(1) 124 96.92
0072 Edit Distance Hard Top_100_Liked_Questions, String, Dynamic_Programming, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_19, Udemy_Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) 51 95.38
0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Algorithm_I_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_2, Level_1_Day_10_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 15 94.90
0064 Minimum Path Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Dynamic_Programming_I_Day_16, Udemy_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(m*n) 74 94.37
0062 Unique Paths Medium Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Algorithm_II_Day_13_Dynamic_Programming, Dynamic_Programming_I_Day_15, Level_1_Day_11_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(m*n) 16 93.42
0056 Merge Intervals Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Data_Structure_II_Day_2_Array, Level_2_Day_17_Interval, Udemy_2D_Arrays/Matrix, Big_O_Time_O(n_log_n)_Space_O(n) 149 89.48
0055 Jump Game Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Algorithm_II_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_4, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) 189 38.02
0053 Maximum Subarray Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Data_Structure_I_Day_1_Array, Dynamic_Programming_I_Day_5, Udemy_Famous_Algorithm, Big_O_Time_O(n)_Space_O(1) 270 38.35
0051 N-Queens Hard Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(N!)_Space_O(N) 106 96.34
0049 Group Anagrams Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Data_Structure_II_Day_8_String, Programming_Skills_II_Day_11, Udemy_Strings, Big_O_Time_O(n*k_log_k)_Space_O(n) 145 96.20
0048 Rotate Image Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Data_Structure_II_Day_3_Array, Programming_Skills_II_Day_7, Udemy_2D_Arrays/Matrix, Big_O_Time_O(n^2)_Space_O(1) 92 97.78
0046 Permutations Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Algorithm_I_Day_11_Recursion_Backtracking, Level_2_Day_20_Brute_Force/Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(n*n!)_Space_O(n+n!) 96 96.56
0045 Jump Game II Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Algorithm_II_Day_13_Dynamic_Programming, Dynamic_Programming_I_Day_4, Big_O_Time_O(n)_Space_O(1) 85 88.80
0042 Trapping Rain Water Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Dynamic_Programming_I_Day_9, Udemy_Two_Pointers, Big_O_Time_O(n)_Space_O(1) 81 89.96
0041 First Missing Positive Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Udemy_Arrays, Big_O_Time_O(n)_Space_O(n) 178 36.64
0039 Combination Sum Medium Top_100_Liked_Questions, Array, Backtracking, Algorithm_II_Day_10_Recursion_Backtracking, Level_2_Day_20_Brute_Force/Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n+2^n) 94 99.60
0035 Search Insert Position Easy Top_100_Liked_Questions, Array, Binary_Search, Algorithm_I_Day_1_Binary_Search, Binary_Search_I_Day_2, Big_O_Time_O(log_n)_Space_O(1) 64 95.18
0034 Find First and Last Position of Element in Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_5, Big_O_Time_O(log_n)_Space_O(1) 120 81.66
0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_11, Level_2_Day_8_Binary_Search, Udemy_Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 63 96.89
0032 Longest Valid Parentheses Hard Top_100_Liked_Questions, String, Dynamic_Programming, Stack, Big_O_Time_O(n)_Space_O(1) 49 96.18
0031 Next Permutation Medium Top_100_Liked_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 98 94.17
0025 Reverse Nodes in k-Group Hard Top_100_Liked_Questions, Linked_List, Recursion, Data_Structure_II_Day_13_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(k) 75 86.97
0024 Swap Nodes in Pairs Medium Top_100_Liked_Questions, Linked_List, Recursion, Data_Structure_II_Day_12_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(1) 58 98.51
0023 Merge k Sorted Lists Hard Top_100_Liked_Questions, Top_Interview_Questions, Heap_Priority_Queue, Linked_List, Divide_and_Conquer, Merge_Sort, Big_O_Time_O(k*n*log(k))_Space_O(log(k)) 78 98.24
0022 Generate Parentheses Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n) 81 99.57
0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Data_Structure_I_Day_7_Linked_List, Algorithm_I_Day_10_Recursion_Backtracking, Level_1_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(m+n)_Space_O(m+n) 69 92.74
0020 Valid Parentheses Easy Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Data_Structure_I_Day_9_Stack_Queue, Udemy_Strings, Big_O_Time_O(n)_Space_O(n) 53 96.68
0019 Remove Nth Node From End of List Medium Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Algorithm_I_Day_5_Two_Pointers, Level_2_Day_3_Linked_List, Big_O_Time_O(L)_Space_O(L) 69 90.79
0017 Letter Combinations of a Phone Number Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(4^n)_Space_O(n) 108 95.24
0015 3Sum Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Data_Structure_II_Day_1_Array, Algorithm_II_Day_3_Two_Pointers, Udemy_Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2) 173 75.85
0011 Container With Most Water Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Greedy, Two_Pointers, Algorithm_II_Day_4_Two_Pointers, Big_O_Time_O(n)_Space_O(1) 251 30.70
0010 Regular Expression Matching Hard Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Recursion, Udemy_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(m*n) 59 96.10
0009 Palindrome Number Easy Math, Udemy_Integers 42 34.61
0008 String to Integer (atoi) Medium Top_Interview_Questions, String 43 99.83
0007 Reverse Integer Medium Top_Interview_Questions, Math, Udemy_Integers 23 59.02
0006 Zigzag Conversion Medium String 59 99.87
0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Data_Structure_II_Day_9_String, Algorithm_II_Day_14_Dynamic_Programming, Dynamic_Programming_I_Day_17, Udemy_Strings, Big_O_Time_O(n)_Space_O(n) 61 99.50
0004 Median of Two Sorted Arrays Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Divide_and_Conquer, Big_O_Time_O(log(min(N,M)))_Space_O(1) 83 96.35
0003 Longest Substring Without Repeating Characters Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Algorithm_I_Day_6_Sliding_Window, Level_2_Day_14_Sliding_Window/Two_Pointer, Udemy_Strings, Big_O_Time_O(n)_Space_O(1) 50 98.40
0002 Add Two Numbers Medium Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Data_Structure_II_Day_10_Linked_List, Programming_Skills_II_Day_15, Big_O_Time_O(max(N,M))_Space_O(max(N,M)) 84 77.30
0001 Two Sum Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Data_Structure_I_Day_2_Array, Level_1_Day_13_Hashmap, Udemy_Arrays, Big_O_Time_O(n)_Space_O(n) 134 81.26