#include <bits/stdc++.h>
using namespace std;
int main() {
  int k = 0;
  int e = 0;
  int y = 0;
  int n = 0;
  int c = 0;
  int e_two = 0;
  int e_three = 0;
  bool e_twocou = false;
  int notkenc = 0;
  int renotkenc = 0;
  bool ans = false;
  string S;
  cin >> S;
  int SL = S.size();
  for (int i = 0; i < SL; i++) {
    if (S[i] == 'k') k++;
    if (S[i] == 'e' && e_two == 1) {
      e_three++;
      e_twocou = true;
    }
    if (S[i] == 'e' && e == 1) {
      e_two++;
      e_twocou = true;
    }
    if (S[i] == 'e' && e_twocou == false) e++;
    e_twocou = false;
    if (S[i] == 'y') y++;
    if (S[i] == 'n') n++;
    if (S[i] == 'c') c++;
    if (S[i] != 'k' && S[i] != 'e' && S[i] != 'y' && S[i] != 'n' &&
        S[i] != 'c' && notkenc >= 1) {
      renotkenc++;
    }
    if (S[i] == 'k' && k > 1 && notkenc >= 1) {
      renotkenc++;
    }
    if (S[i] == 'e' && e > 1 && notkenc >= 1) {
      renotkenc++;
    }
    if (S[i] == 'y' && y > 1 && notkenc >= 1) {
      renotkenc++;
    }
    if (S[i] == 'n' && n > 1 && notkenc >= 1) {
      renotkenc++;
    }
    if (S[i] == 'c' && c > 1 && notkenc >= 1) {
      renotkenc++;
    }
    if (S[i] != 'k' && S[i] != 'e' && S[i] != 'y' && S[i] != 'n' &&
        S[i] != 'c') {
      notkenc++;
      if (S[i + 1] != 'k' && S[i + 1] != 'e' && S[i + 1] != 'y' &&
          S[i + 1] != 'n' && S[i + 1] != 'c')
        notkenc = 0;
    }
    if (S[i] == 'k' && k > 1) {
      notkenc++;
    }
    if (S[i] == 'e' && e > 1) {
      notkenc++;
    }
    if (S[i] == 'y' && y > 1) {
      notkenc++;
    }
    if (S[i] == 'n' && n > 1) {
      notkenc++;
    }
    if (S[i] == 'c' && c > 1) {
      notkenc++;
    }
    if (S[i + 1] == 'k' && k > 1) {
      notkenc = 0;
    }
    if (S[i + 1] == 'e' && e > 1) {
      notkenc = 0;
    }
    if (S[i + 1] == 'y' && y > 1) {
      notkenc = 0;
    }
    if (S[i + 1] == 'n' && n > 1) {
      notkenc = 0;
    }
    if (S[i + 1] == 'c' && c > 1) {
      notkenc = 0;
    }
    if (i = S.size() - 1) {
      if (S[i] != 'k' && S[i] != 'e' && S[i] != 'y' && S[i] != 'n' &&
          S[i] != 'c' && notkenc >= 1) {
        renotkenc++;
      }
    }
  }
  if (k > 0 && e > 0 && y > 0 && n > 0 && c > 0 && e_two > 0 && e_three > 0) {
    if (renotkenc == 0) ans = true;
  }
  if (ans)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  cin >> e;
  return 0;
}
