长度最小的子数组

[JesseZhao1990]

/**
 * @param {number} s
 * @param {number[]} nums
 * @return {number}
 */
var minSubArrayLen = function(s, nums) {
    var l = 0;
    var r = -1;
    var sum = 0;
    var length = nums.length;
    var res = length+1;
    
    while(l<length){
        if(r+1<length && sum<s){
            sum = sum + nums[++r];
        }else{
            sum = sum - nums[l++];
        }
        
        if(sum>=s){
            res = Math.min(r-l+1,res);
        }
    }
    
    if(res == length+1) return 0;  // 遍历一遍之后发现无解的时候返回0
    
    return res
    
};

leetcode原题地址：https://leetcode-cn.com/problems/minimum-size-subarray-sum/description/