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 Kotlin (1.0.0) (judge verdict: Accepted)

fun main(args: Array<String>) {
    val strings = readLine()!!
    val keyence = "keyence"
    val length = strings.length
    if (length < 7) {
        print("NO")
    } else {
        var firstCount = 0
        var secondCount = 0
        val charKeyence = keyence.toCharArray()
        run loop@{
            strings.subSequence(0, 7).forEach {
                if (it == charKeyence[firstCount]) {
                    firstCount++
                } else {
                    return@loop
                }
            }
        }
        run loop@{
            strings.subSequence(length - 7, length).reversed().forEach {
                if (it == charKeyence[7 - secondCount - 1]) {
                    secondCount++
                } else {
                    return@loop
                }
            }
        }
        if (firstCount + secondCount >= 7) {
            print("YES")
        } else {
            print("NO")
        }
    }
}