Smallest Subarray With a Greater Sum

Given an array of positive integers and a number ‘S,’ find the length of the smallest contiguous subarray whose sum is greater than or equal to 'S'. Return 0 if no such subarray exists.

Example 1:

• Input: arr = [2, 1, 5, 2, 3, 2], S = 7
• Output: 2

  class Solution {
    public int minSubArrayLen(int target, int[] nums) {
        var windowStart = 0;
        var minLength = Integer.MAX_VALUE;
        var windowSum = 0;
        for (int windowEnd = 0; windowEnd < nums.length; windowEnd ++) {
            windowSum += nums[windowEnd];
            while (windowSum >= target) {
                minLength = Math.min((windowEnd - windowStart + 1), minLength);
                windowSum -= nums[windowStart];
                windowStart ++;
            }
        }
        return minLength != Integer.MAX_VALUE
            ? minLength
            : 0;
    }
}