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 Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.Scanner;
public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		String keyence = "keyence";
		String[][] keyarr = new String[8][2];
		for(int i = 0;i < 8;i ++) {
			keyarr[i][0] = keyence.substring(0, i);
			keyarr[i][1] = keyence.substring(i, 7);
			System.out.println(s.indexOf(keyarr[i][1]));
			if(i < 7) {
				if(s.indexOf(keyarr[i][0]) == 0 && 
						s.indexOf(keyarr[i][1]) == s.length() - keyarr[i][1].length()) {
					System.out.println("YES");
					return;
				}
			}else {
				if(s.indexOf(keyarr[i][0]) == 0 && 
						s.indexOf(keyarr[i][1]) == 0) {
					System.out.println("YES");
					return;
				}
			}
		}
		System.out.println("NO");
	}
}