import java.io.*; import java.util.*; import java.util.stream.*; public class Main { static final int MOD = 1000000007; public static void main(String[] args) throws Exception { Scanner sc = new Scanner(); int n = sc.nextInt(); char[] inputs = sc.next().toCharArray(); char[] yukicoder = "yukicoder".toCharArray(); HashMap idxes = new HashMap<>(); for (int i = 0; i < yukicoder.length; i++) { idxes.put(yukicoder[i], i + 1); } int[][] counts = new int[yukicoder.length + 1][2]; counts[0][0] = 1; for (char c : inputs) { if (idxes.containsKey(c)) { int i = idxes.get(c); counts[i][0] += counts[i - 1][0]; counts[i][0] %= MOD; counts[i][1] += counts[i - 1][1]; counts[i][1] %= MOD; } else if (c == '?') { for (int i = 1; i <= yukicoder.length; i++) { counts[i][1] += counts[i - 1][0]; counts[i][1] %= MOD; } } } System.out.println((counts[yukicoder.length][0] + counts[yukicoder.length][1]) % MOD); } } class Utilities { static String arrayToLineString(Object[] arr) { return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n")); } static String arrayToLineString(int[] arr) { return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new)); } } class Scanner { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer st = new StringTokenizer(""); StringBuilder sb = new StringBuilder(); public Scanner() throws Exception { } public int nextInt() throws Exception { return Integer.parseInt(next()); } public long nextLong() throws Exception { return Long.parseLong(next()); } public double nextDouble() throws Exception { return Double.parseDouble(next()); } public int[] nextIntArray() throws Exception { return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray(); } public String next() throws Exception { while (!st.hasMoreTokens()) { st = new StringTokenizer(br.readLine()); } return st.nextToken(); } }