package main

import . "fmt"

func main() {
	var n int
	var s string
	Scan(&n,&s)
	dp := make([][]int, 2)
	for i := range dp {
		dp[i] = make([]int, len("yukicoder")+1)
	}
	const Mod int = 1e9+7
	t := make(map[rune]int)
	for i, ch := range "yukicoder" {
		t[ch] = i
	}
	dp[0][0] = 1
	for _, ch := range s {
		if i, ok := t[ch]; ok {
			dp[0][i+1] = (dp[0][i+1] + dp[0][i]) % Mod
			dp[1][i+1] = (dp[1][i+1] + dp[1][i]) % Mod
		} else if ch == '?' {
			for j := 0; j < len(t); j++ {
				dp[1][j+1] = (dp[1][j+1] + dp[0][j]) % Mod
			}
		}
	}
	ans := (dp[0][len(t)] + dp[1][len(t)]) % Mod
	Println(ans)
}