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.chars
kes = "keyence_"
d = []
str = ""
i = 0
s.each do |c|
  if kes[i] == c
    d << str if str != ""
    str = ""
    i += 1
  else
    str += c
  end
end
d << str if str != ""
puts (i == 7 && d.size <= 1)? "YES" : "NO"