Problem:
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The Smallest Window I

For a given array $a_1, a_2, a_3, ... , a_N$ of $N$ elements and an integer $S$, find the smallest sub-array size (smallest window length) where the sum of the sub-array is greater than or equal to $S$. If there is not such sub-array, report 0.

Constraints

$1 \leq N \leq 10^5$

$1 \leq S \leq 10^9$

$1 \leq a_i \leq 10^4$

Input

The input is given in the following format.

$N$ $S$

$a_1$ $a_2$ ... $a_N$

Output

Print the smallest sub-array size in a line.

Sample Input 1

6 4
1 2 1 2 3 2

Sample Output 1

2

Sample Input 2

6 6
1 2 1 2 3 2

Sample Output 2

3

Sample Input 3

3 7
1 2 3

Sample Output 3

0

Solution in C (judge verdict: Accepted)

#include <stdio.h>          // printf(), scanf()
#include <stdbool.h>

#define MAX_N 100000
#define min(a, b) ((a) < (b) ? (a) : (b))

int a[MAX_N];
int S;
int n;

int
solve()
{
	int s, t;

	int res = n + 1;
	int sum = 0;
	s = 0, t = 0;
	while (true)
	{
		while (t < n && sum < S)
			sum += a[t++];

		if (sum < S)
			break;

		res = min(res, t - s);
		sum -= a[s++];
	}

	if (res > n)
		return 0;

	return res;
}

int
main(int argc, char** argv)
{
	int i;

	scanf("%d %d", &n, &S);
	for (i = 0; i < n; ++i)
		scanf("%d", &a[i]);

	printf("%d\n", solve());
	return 0;
}