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 Ruby (2.3.3) (judge verdict: Time Limit Exceeded)

ARGF.each { |line|
  s = line.chop

  keystr = "keyence"

  i = 0
  while keystr[i] == s[i]
    i += 1
  end
  j = 1
  while keystr[7-j] == s[s.size-j]
    j += 1
  end

  if i+j > 7
    puts "YES"
  else
    puts "NO"
  end
  exit
}