#include <bits/stdc++.h>
using namespace std;
int main(void) {
  string str;
  long int c[200];
  cin >> str;
  for (long int i = 0; i < str.length(); i++) {
    c[str[i]]++;
  }
  if (c['k'] > 0 && c['e'] >= 3 && c['y'] > 0 && c['n'] > 0 && c['c'] > 0) {
    cout << "YES" << endl;
  } else {
    cout << "NO" << endl;
  }
  return 0;
}
