#include <bits/stdc++.h>
using namespace std;
bool prime(long long n) {
  long long cnt = 0;
  for (long long i = 1; i <= sqrt(n); i++) {
    if (n % i == 0) cnt++;
  }
  if (cnt != 1)
    return false;
  else
    return n != 1;
}
long long gcd(long long x, long long y) {
  long long ans;
  for (long long i = (min(x, y)); i >= 1; i--) {
    if (x % i == 0 && y % i == 0) {
      ans = i;
      break;
    }
  }
  return ans;
}
long long yakusuunowa(long long n) {
  long long ans = 0;
  for (long long i = 1; i <= n; i++) {
    if (n % i == 0) ans += i;
  }
  return ans;
}
long long lcm(long long x, long long y) { return x * y / gcd(x, y); }
long long ketanowa(long long n) {
  long long cnt = 0, sum = 0;
  for (long long i = 10; i <= n * 10; i *= 10) {
    if (i == 10)
      cnt += n % i;
    else
      sum += (n % i - n % (i / 10)) / (i / 10);
  }
  return cnt + sum;
}
signed main() {
  long long sa = -1, san = 0, sana = 0, sanad = 0, sanada = 0, sanaday = 0,
            sanadayu = 0;
  string s;
  cin >> s;
  for (long long i = 0; i < s.size(); i++) {
    if (s[i] == 'k') {
      sa = i;
      break;
    }
  }
  if (sa == -1) {
    puts("NO");
    return 0;
  }
  for (long long j = sa + 1; j < s.size(); j++) {
    if (s[j] == 'e') {
      san = j;
      break;
    }
  }
  if (san == 0) {
    puts("NO");
    return 0;
  }
  for (long long k = san + 1; k < s.size(); k++) {
    if (s[k] == 'y') {
      sana = k;
      break;
    }
  }
  if (sana == 0) {
    puts("NO");
    return 0;
  }
  for (long long l = sana + 1; l < s.size(); l++) {
    if (s[l] == 'e') {
      sanad = l;
      break;
    }
  }
  if (sanad = 0) {
    puts("NO");
    return 0;
  }
  for (long long m = sanad + 1; m < s.size(); m++) {
    if (s[m] == 'n') {
      sanada = m;
      break;
    }
  }
  if (sanada = 0) {
    puts("NO");
    return 0;
  }
  for (long long o = sanada + 1; o < s.size(); o++) {
    if (s[o] == 'c') {
      sanaday = o;
      break;
    }
  }
  if (sanaday == 0) {
    puts("NO");
    return 0;
  }
  for (long long p = sanaday + 1; p < s.size(); p++) {
    if (s[p] == 'e') {
      sanadayu = p;
      break;
    }
  }
  if (sanadayu == 0) {
    puts("NO");
    return 0;
  }
  puts("YES");
  getchar();
  getchar();
  return 0;
}
