1806번 부분합

전 문제에 이어서 약간만 수정하였다.

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;
int n, m;
int main() {
	//freopen("in1.txt", "rt", stdin);
	int cnt = 0;
	cin >> n >> m;
	vector<int> arr(n+1);
	for (int i = 0; i < n; i++) {
		cin >> arr[i];
	}
	int lt = 0, rt = 0;
	int len = 2147000000;
	int sum = arr[0];
	while (rt<n) {
		//cout << "error " <<"rt:"<< rt<< " sum"<<sum<<'\n';
		if (sum <= m) {
			if(sum == m) len = min(len, rt - lt + 1);
			rt++;
			if (rt == n) break;
			sum += arr[rt];
		}
		if (sum > m) {
			sum -= arr[lt];
			len = min(len, rt - lt + 1);
			lt++;
			if (lt > rt) {
				rt = lt;
			}

		}

	}
	if (len == 2147000000) cout << "0" << '\n';
	else cout << len << '\n';
	return 0;
}