#include <bits/stdc++.h>

using namespace std;

int solve(vector <int> A) {
    //  Return the sum of S(S(A)) modulo 10^9+7.
    return 0;
}

int main() {
    int n;
    cin >> n;
    vector<int> A(n);
    for(int A_i = 0; A_i < n; A_i++){
       cin >> A[A_i];
    }
    int result = solve(A);
    cout << result << endl;
    return 0;
}