백준 1806 - 부분 합

https://www.acmicpc.net/problem/1806

1806번: 부분합

#include <iostream>
#include <queue>
#include <vector>
#include <math.h>
using namespace std;
int N, S, minLength, L, R;
vector<int> num;
int main() {
	L = 0;
	R = 0;
	cin >> N >> S;
	minLength = N + 1;
	for (int i = 0; i < N; i++) {
		int key;
		cin >> key;
		num.push_back(key);
	}

	int sum = 0;
	L = 0;
	R = 0;
	sum = num[0];
	while (L <= R && R < N) {
		if (sum < S) {
			R += 1;
			if(R < N)
			sum += num[R];
		}
		else {
			minLength = min(minLength, R - L + 1);
			sum -= num[L++];
		}
	}

	if (minLength == N + 1)
		minLength = 0;

	cout << minLength << endl;
	return 0;
}

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