Problem: 

Input

The input consists of a single string of uppercase letters A-Z. The length of the string is between 1 and 10 characters, inclusive.

Output

Output "YES" or "NO".

Examples

Input


GENIUS


Output


YES


Input


DOCTOR


Output


NO


Input


IRENE


Output


YES


Input


MARY


Output


NO


Input


SMARTPHONE


Output


NO


Input


REVOLVER


Output


YES


Input


HOLMES


Output


NO


Input


WATSON


Output


YES

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
long long mod = 1e9 + 7;
int dx[] = {1, -1, 0, 0};
int dy[] = {0, 0, 1, -1};
using namespace std;
int c = 0;
long long pow(long long a, long long b) {
  long long ans = 1;
  if (b == 0) return 1;
  ans *= pow(a, b / 2);
  ans = ((ans % mod) * (ans % mod)) % mod;
  if (b & 1) {
    ans = ((ans % mod) * a);
    ans %= mod;
  }
  return ans % mod;
}
long long gcd(long long a, long long b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
vector<long long> fac(1e6 + 5, -1);
long long fact(long long n) {
  if (n <= 1) return fac[n] = 1ll;
  if (fac[n] > 0) return fac[n];
  fac[n] = n * fact(n - 1);
  fac[n] %= mod;
  return fac[n];
}
long long nCr(long long n, long long r) {
  if (n == r || r == 0) return 1;
  long long ans = fac[n];
  ans *= pow(fac[n - r], mod - 2);
  ans %= mod;
  ans *= pow(fac[r], mod - 2);
  ans %= mod;
  return ans;
}
const long long nax = 1e5 + 3;
void solve() {
  string s;
  cin >> s;
  int n = s.size();
  for (int i = 2; i < n; i++) {
    if (s[i] != 'A' + ((s[i - 2] - 'A') + (s[i - 1] - 'A')) % 26) {
      cout << "NO" << endl;
      return;
    }
  }
  cout << "YES" << endl;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  ;
  int q = 1;
  while (q--) {
    c++;
    solve();
  }
}