#include <bits/stdc++.h>

using namespace std;
using ll = long long;

const int N = 1e5 + 10;
const ll INF = 2e18;

int n, top;
ll p, a[N], stk[N];
__int128 sum;

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    cin >> n >> p;
    for (int i = 1; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= n; i++) {
        int pos = i;
        while (top && a[stk[top]] > a[i]) {
            sum -= a[stk[top]] * (pos - stk[top]);
            pos = stk[top], top--;
        }
        sum += (i - stk[top]) * a[i], stk[++top] = i;

        sum += a[i] - 1;
        if (sum + 2 * a[i + 1] >= p) {
            cout << i; return 0;
        }
    }
    cout << n;
    return 0;
}