Problem:
Score : 200 points

Problem Statement

A string is called a KEYENCE string when it can be changed to keyence by removing its contiguous substring (possibly empty) only once.

Given a string S consisting of lowercase English letters, determine if S is a KEYENCE string.

Constraints

The length of S is between 7 and 100 (inclusive).

S consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S

Output

If S is a KEYENCE string, print YES; otherwise, print NO.

Sample Input 1

keyofscience

Sample Output 1

YES

keyence is an abbreviation of key of science.

Sample Input 2

mpyszsbznf

Sample Output 2

NO

Sample Input 3

ashlfyha

Sample Output 3

NO

Sample Input 4

keyence

Sample Output 4

YES

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;

class Program
{
  public static void Main()
  {
    string S = Console.ReadLine();
    Console.WriteLine(judge(S) ? "YES" : "NO");
  }
  public static bool judge(string s) {
    for (int i = 0; i < s.Length-1; i ++) {
      for (int j = 0; j <= s.Length - i; j ++) {
        if(s.Remove(i, j) == "keyence") return true;
      }
    }
    return false;
  }
}