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)

s = gets.chomp
key = "keyence"

if s[0] != "k" || s[-1] != "e"
    puts s =~ /#{key}/ ? "YES" : "NO"
else
    i = 0
    i += 1 while i < 8 && s[i] == key[i]
    j = 0
    j += 1 while j < 8 && s[-j] == key[-j]

    puts i + j >= 8 ? "YES" : "NO"
end