Given an array of n positive integers and a positive integer s, find the minimal length of a contiguous subarray of which the sum ≥ s. If there isn't one, return 0 instead.
Example:
Input: s = 7, nums = [2,3,1,2,4,3]
Output: 2
Explanation: the subarray [4,3] has the minimal length under the problem constraint.
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:
class Solution {
public int minSubArrayLen(int s, int[] nums) {
int left = 0;
int right = 0;
int min = Integer.MAX_VALUE;
int sum = 0;
while (right <= nums.length - 1) {
int curr = nums[right];
sum += curr;
while (left <= right && sum >= s) {
min = Math.min(min, right - left + 1);
int leftVal = nums[left ++];
sum -= leftVal;
}
right ++;
}
return min == Integer.MAX_VALUE ? 0 : min;
}
}