#include <bits/stdc++.h>
using namespace std;
int main() {
  long long i, j, k = 0, y = 0, e = 0, n = 0, c = 0;
  string s;
  cin >> s;
  for (i = 0; i < s.size(); i++) {
    if (s[i] == 'k')
      k++;
    else if (s[i] == 'e')
      e++;
    else if (s[i] == 'y')
      y++;
    else if (s[i] == 'n')
      n++;
    else if (s[i] == 'c')
      c++;
  }
  if (k >= 1 && e >= 3 && y >= 1 && n >= 1 && c >= 1)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  return 0;
}
