#include <iostream>
#include <vector>
#include <bits/stdc++.h>

using namespace std;

int main()
{
    int n;
    long k;
    long b;
    cin >> n;
    cin >> k;
    cin >> b;

    vector<long> hehe = {};

    int negatives = 0;

    for (int i = 0; i < n; i++) {
        long x;
        cin >> x;

        if (x <= 0) {
            negatives += 1;
        }

        hehe.push_back(x);
    }

    sort(hehe.begin(), hehe.end());

    for (int i = negatives - 1; i >= b; i--) {
        long z = -hehe[i];
        hehe[i] += z;
        k -= z;
    }

    if (k < 0) {
        cout << -1 << endl;
    }
    else {

        int x = b;

        while (k > 0) {
            hehe[x] += 1;
            k -= 1;
            x += 1;
            if (x == n || hehe[x] >= hehe[x - 1]) {
                x = b;
            }
        }

        long f = 1;

        for (int i = 0; i < n; i++) {
            f = (hehe[i] * f) % 1000000007;
        }

        cout << f << endl;
    }

    return 0;
}