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

constexpr long long MOD = 998244353;

int main() {
  int n; string s;
  cin >> n >> s;

  if (n % 10 != 0) {
    cout << 0 << endl;
    return 0;
  }
  
  vector<long long> dp(n / 10 + 1);
  dp[0] = 1;

  for (int i = 0; i < n / 10; i++) {
    for (int k = 1; k <= n / 10 - i; k++) {
      bool ok = true;
      if (s[i * 10 + 2 * k] == 'x') ok = false;
      if (s[i * 10 + (2 + 3) * k] == 'x') ok = false;
      if (s[i * 10 + (2 + 3 + 5) * k] == 'x') ok = false;

      if (ok) {
        dp[i + k] += dp[i];
        dp[i + k] %= MOD;
      }
    }
  }

  cout << dp[n / 10] << endl;
}