LeetCode in Net
209. Minimum Size Subarray Sum
Medium
Given an array of positive integers nums and a positive integer target, return the minimal length of a contiguous subarray [numsl, numsl+1, ..., numsr-1, numsr] of which the sum is greater than or equal to target. If there is no such subarray, return 0 instead.
Example 1:
Input: target = 7, nums = [2,3,1,2,4,3]
Output: 2
Explanation: The subarray [4,3] has the minimal length under the problem constraint.
Example 2:
Input: target = 4, nums = [1,4,4]
Output: 1
Example 3:
Input: target = 11, nums = [1,1,1,1,1,1,1,1]
Output: 0
Constraints:
1 <= target <= 1091 <= nums.length <= 1051 <= nums[i] <= 105
Follow up: If you have figured out the O(n) solution, try coding another solution of which the time complexity is O(n log(n)).
Solution
public class Solution {
public int MinSubArrayLen(int target, int[] nums) {
int i = 0, j = 0, sum = 0, min = int.MaxValue;
while (j < nums.Length) {
sum += nums[j];
if (sum >= target) {
while (i <= j) {
if (sum - nums[i] >= target) {
sum -= nums[i];
i++;
} else {
break;
}
}
if (j - i + 1 < min) {
min = j - i + 1;
}
}
j++;
}
return min == int.MaxValue ? 0 : min;
}
}