#include <bits/stdc++.h>
using namespace std;
vector<char> v;
int main() {
  string s;
  cin >> s;
  int sum1 = 0, sum2 = 0, sum3 = 0, sum4 = 0, sum5 = 0;
  for (int i = 0; i < s.size(); i++) {
    if (s[i] == 'k') {
      if (sum1 == 1) {
        continue;
      } else {
        v.push_back(s[i]);
        sum1++;
      }
    }
    if (s[i] == 'e') {
      if (sum2 == 3) {
        continue;
      } else {
        v.push_back(s[i]);
        sum2++;
      }
    }
    if (s[i] == 'y') {
      if (sum3 == 1) {
        continue;
      } else {
        v.push_back(s[i]);
        sum3++;
      }
    }
    if (s[i] == 'n') {
      if (sum4 == 1) {
        continue;
      } else {
        v.push_back(s[i]);
        sum4++;
      }
    }
    if (s[i] == 'c') {
      if (sum5 == 1) {
        continue;
      } else {
        v.push_back(s[i]);
        sum5++;
      }
    }
  }
  sort(v.begin(), v.end());
  if (v[0] == 'c' && v[1] == 'e' && v[2] == 'e' && v[3] == 'e' && v[4] == 'k' &&
      v[5] == 'n' && v[6] == 'y') {
    cout << "YES";
  } else {
    cout << "NO";
  }
  return 0;
}
