#include <bits/stdc++.h>
using namespace std;
int main() {
  long long i, j, k, a, b, c = 0, d = 0, n = 0, m = 0, t = 1, x = 0;
  string s;
  cin >> s;
  for (i = 0; i < s.size(); i++) {
    if (s[i] == 'k')
      c++;
    else if (s[i] == 'e')
      d++;
    else if (s[i] == 'y')
      n++;
    else if (s[i] == 'n')
      m++;
    else if (s[i] == 'c')
      x++;
  }
  if (c >= 1 && d >= 3 && n >= 1 && m >= 1 && x >= 1)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  return 0;
}
