백준 1806 - 투포인터

#include <iostream>
#include <vector>
#include <queue>
#include <climits>
#include <algorithm>

using namespace std;

int main(void)
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);	cout.tie(0);

	int n, s;

	cin >> n >> s;

	vector<int> arr(n);

	for (int i = 0; i < n; ++i)
	{
		cin >> arr[i];
	}

	int startIdx = 0;
	int endIdx = 0;

	int ans = INT_MAX;

	int sum = 0;
	sum += arr[startIdx];

	while (startIdx < n)
	{
		if (sum >= s)
		{
			int num = endIdx - startIdx + 1;
			sum -= arr[startIdx];
			startIdx++;
			if (ans > num)
			{
				ans = num;
			}
		}
		else if (sum < s)
		{
			if (endIdx < n - 1)
			{
				endIdx++;
				sum += arr[endIdx];
			}
			else
			{
				sum -= arr[startIdx];
				startIdx++;
			}
		}
	}

	if (ans == INT_MAX)
	{
		cout << 0;
	}
	else
	{
		cout << ans;

	}

	return 0;
}