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: Accepted)

a = "keyence"
s = gets.chomp

f = a.size.times.map{|i|a[i]==s[i]}
r = a.size.times.map{|i|a[-1-i]==s[-1-i]}

ans = 0
f.each{|b|
  break if !b
  ans+=1
}
r.each{|b|
  break if !b
  ans+=1
}

puts (ans>=7)? "YES":"NO"