#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n,b; long long k; //ifstream f("szamok.txt");
    cin>>n>>k>>b; vector<int>a(n);
    for(int i=0; i<n; i++)cin>>a[i];
    sort(a.begin(),a.end());
    if(b!=0 && a[b-1]>=0){cout<<-1; return 0;}
    long long s=0,t=b;
    if(n!=b){
        while(k>s+(a[t]-a[t-1])*(t-b) && t<n){
            s+=(a[t]-a[t-1])*(t-b);
            t++;}
        for(int i=b; i<t; i++)a[i]=a[t-1];
        k-=s;
        for(int i=b; i<t; i++)a[i]+=k/(t-b);
        k=k%(t-b);
        for(int i=b; i<b+k; i++)a[i]++;
        if(a[b]<0){cout<<-1; return 0;}}
    else{
        for(int i=0; i<k; i++){
            a[0]++; int r=0;
            while(a[r]>a[r+1]){swap(a[r],a[r+1]); r++;}}
        if(a[n-1]>=0){cout<<-1; return 0;}}
    s=1; int mod=1000000007;
    for(int i=0; i<n; i++)s=(s*a[i])%mod;
    cout<<s;
    return 0;
}