#include <bits/stdc++.h>
using namespace std;
string s, prim = "WETYIAFHKLZXVNM";
set<char> myset;
bool fin = false, fnotin = false;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> s;
  for (int i = 0; i < prim.size(); i++) myset.insert(prim[i]);
  for (int i = 0; i < s.size(); i++)
    if (myset.find(s[i]) != myset.end())
      fin = true;
    else
      fnotin = true;
  if (fin + fnotin == 1)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
