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 Perl (v5.18.2) (judge verdict: Wrong Answer)

$a = "k";
@b = split(//, "eyence");

chomp($s = <>);
if($s =~ /keyence$/){
	$r = "YES";
}elsif($s =~ /^k/){
	if($s =~ /^keyence/){
		$r = "YES";
	}else{
		for (1 .. 5){
			$a .= shift(@b);
			$str = join("", @b);
			if($s =~ /^$a.*$str$/){
				$r = "YES";
				last;
			}
		}
	}
}else{
	$r = "NO";
}

print "$r\n";