LeetCode 0209 - Minimum Size Subarray Sum

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.

class Solution {
public:
    int minSubArrayLen(int s, vector<int>& nums) {
        int left = 0;
        int right = 0;
        int res = INT_MAX;
        int sum = 0;
        while(right < nums.size()) {
            sum += nums[right++];
            while(sum >= s) {
                res = min(res, right - left);
                sum -= nums[left++];
            }
        }
        return res==INT_MAX?0:res;
    }
};