leetcode209. Minimum Size Subarray Sum

209. Minimum Size Subarray Sum

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.

For example, given the array [2,3,1,2,4,3] and s = 7,
the subarray [4,3] has the minimal length under the problem constraint.

解法

public class Solution {    public int minSubArrayLen(int s, int[] nums) {        if (nums == null || nums.length == 0) {            return 0;        }        int sum = 0, len = 0, minLen = Integer.MAX_VALUE;        for (int i = 0; i < nums.length; i++) {            sum += nums[i];            len++;            if (sum >= s) {                if (len < minLen) {                    minLen = len;                }                i = i - len + 1;                len = 0;                sum = 0;            }        }        return minLen != Integer.MAX_VALUE ? minLen : 0;    }}