#include <bits/stdc++.h>
using namespace std;
signed main() {
  string s;
  cin >> s;
  long long flag = 0;
  long long flag2 = 0;
  bool ans = false;
  for (char x : s) {
    if (flag == 0 && x != 'k') {
      flag2 = 1;
    }
    if (flag == 0 && x == 'k') {
      flag = 1;
    }
    if (flag == 1 && x != 'e') {
      if (flag2 == 1) {
        cout << "NO" << endl;
        return 0;
      } else {
        flag2 = 1;
      }
    }
    if (flag == 1 && x == 'e') {
      flag = 2;
    }
    if (flag == 2 && x != 'y') {
      if (flag2 == 1) {
        cout << "NO" << endl;
        return 0;
      } else {
        flag2 = 1;
      }
    }
    if (flag == 2 && x == 'y') {
      flag = 3;
    }
    if (flag == 3 && x != 'e') {
      if (flag2 == 1) {
        cout << "NO" << endl;
        return 0;
      } else {
        flag2 = 1;
      }
    }
    if (flag == 3 && x == 'e') {
      flag = 4;
    }
    if (flag == 4 && x != 'n') {
      if (flag2 == 1) {
        cout << "NO" << endl;
        return 0;
      } else {
        flag2 = 1;
      }
    }
    if (flag == 4 && x == 'n') {
      flag = 5;
    }
    if (flag == 5 && x != 'c') {
      if (flag2 == 1) {
        cout << "NO" << endl;
        return 0;
      } else {
        flag2 = 1;
      }
    }
    if (flag == 5 && x == 'c') {
      flag = 6;
    }
    if (flag == 6 && x != 'e') {
      if (flag2 == 1) {
        cout << "NO" << endl;
        return 0;
      } else {
        flag2 = 1;
      }
    }
    if (flag == 6 && x == 'e') {
      ans = true;
      flag = 7;
    }
    if (flag == 7) {
      if (flag2 == 1) {
        cout << "NO" << endl;
        return 0;
      } else {
        flag2 = 1;
      }
    }
  }
  if (ans) {
    cout << "YES" << endl;
    return 0;
  }
  cout << "NO" << endl;
  return 0;
}
