Leetcode 209. Minimum Size Subarray Sum (Medium) (cpp)

Leetcode 209. Minimum Size Subarray Sum (Medium) (cpp)

Tag: Array, Two Pointers, Binary Search

Difficulty: Medium

/*209. Minimum Size Subarray Sum (Medium)Given an array of n positive integers and a positive integer s, find the minimal length of a 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.click to show more practice.More practice:If you have figured out the O(n) solution, try coding another solution of which the time complexity is O(n log n).*/class Solution {public:int minSubArrayLen(int s, vector<int>& nums) {int left = 0, right = 0, _sum = 0, _size = nums.size(), len_min = _size + 1;while (right < _size) {while (right < _size && _sum < s) _sum += nums[right++];while (_sum >= s) _sum -= nums[left++];len_min = min(len_min, right - left + 1);}return len_min > _size ? 0 : len_min;}};