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 Scala (2.11.7) (judge verdict: Accepted)

import scala.io.{StdIn => in}

object Main extends App {
  val s = in.readLine
  val n = s.size
  val v = "keyence"

  val res = for {
    i <- 0 to 7
    j = 7 - i
    if s.take(i) + s.takeRight(j) == v
  } yield true

  val ans = if(res.nonEmpty) "YES" else "NO"
  println(ans)
}