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Minimum Size Subarray Sum

Problem statement​

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: 2Explanation: 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 <= 109
  • 1 <= nums.length <= 105
  • 1 <= 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)).

My solution​

/**
 * @param {number} s
 * @param {number[]} nums
 * @return {number}
 */
var minSubArrayLen = function(s, nums) {

    let left = 0;
    let right = 0;
    let sum = 0;
    let min = Number.MAX_VALUE;
    while (right <= nums.length) {
        // console.log(left, right, sum);
        if (sum >= s) {
            min = Math.min(min, right - left);
            sum -= nums[left];
            left++;
        } else {    
            sum += nums[right];
            right++;
        }
    }
    return min === Number.MAX_VALUE ? 0 : min;
};

/*

2 => (1 | 3, 1)
3 => (1 | 1, 2)
1 => (0 | 2, 4) // [1, 2, 4]
2 => (1 | 4)
4 => (0 | 3) // [4, 3]

*/