#include <bits/stdc++.h>
using namespace std;

int main() {
	long long n, k, b, ln = -1;
    cin >> n >> k >> b;
    vector <long long> a (n, 0);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    sort(a.begin(), a.end());
    for (int i = 0; i < n; i++) {
        if (a[i] < 0) {
            ln = i;
        }
    }

    if (b > ln+1) {
        cout << -1;
        return 0;
    }
    while (b < ln+1) {
        if (k >= -1*a[ln]) {
            k += a[ln];
            a[ln] = 0;
            ln--;
        } else {
            cout << -1;
            return 0;
        }
    }
    if (ln+1 != n) {
        long long p = ln+1;
        while (k > 0) {
            a[p]++;
            k--;
            if (p+1 != n) {
                if (a[p+1] < a[p]) {
                    p++;
                } else {
                    p = ln + 1;
                }
            } else {
                p = ln + 1;
            }
        }
    } else {
        while (k > 0) {
            int m = INT_MAX, mi = -1;
            for (int i = 0; i < n; i++) {
                if (m > a[i] && a[i] < -1) {
                    m = a[i];
                    mi = i;
                }
            }

            if (mi != -1) {
                a[mi]++;
                k--;
            } else {
                cout << -1;
                return 0;
            }
        }
    }
    

    long long s = 1;
    for (int i = 0; i < n; i++) {
        s *= abs(a[i]);
        s = s % 1000000007;
    }
    cout << s;
	return 0;
}