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: Wrong Answer)

S = gets.chomp
key = "keyence"
ok_flag = false
6.times do |i|
  a = key[0,i+1]
  b = key[i+1,6]
  #puts "i=#{i} a=#{a} b=#{b}"
  apos = S.index(a)
  bpos = S.index(b)
  if apos!=nil && bpos!=nil && apos < bpos then
    #puts "YES"
    ok_flag = true
    break
  end
end

if ok_flag then
  puts "YES"
else
  puts "NO"
end