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

constexpr int mod = 1000000007;
int dp[100005][11][2];

int main() {
    int N;
    string S;
    cin >> N >> S;
    dp[0][0][0] = 1;
    string B = "yukicoder";
    for(int i = 0; i < N; i++) {
        for(int j = 0; j <= 9; j++) {
            for(int k = 0; k < 2; k++) {
                if(k == 0 && S[i] == '?') {
                    dp[i+1][j+1][1] += dp[i][j][k];
                    dp[i+1][j+1][1] %= mod;
                }
                if(j < 9 && S[i] == B[j]) {
                    dp[i+1][j+1][k] += dp[i][j][k];
                    dp[i+1][j+1][k] %= mod;
                }
                dp[i+1][j][k] += dp[i][j][k];
                dp[i+1][j][k] %= mod;
            }
        }
    }
    cout << (dp[N][9][0]+dp[N][9][1])%mod << endl;
}