#include <bits/stdc++.h>

using namespace std;

int main()
{
    int n, target;
    cin >> n >> target;
    vector<int> vec(n, 0);
    for (int i=0; i < n; i++) {
        cin >> vec[i];
    }

    int low = 0, high = -1;
    int t = 0;
    int res = n + 1;

    while (high < n) {
        if (t < target) {
            high++;
            if (high < n) {
                t += vec[high];
            }
        } else {
            t -= vec[low];
            low++;
        }
        if (t >= target) {
            if (high - low + 1 < res) {
                res = high - low + 1;
            }
        }
    }

    if (res == n + 1) {
        cout << -1 << '\n';
    } else {
        cout << res << '\n';
    }

    return 0;
}