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: Accepted)

import java.util.*;

class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String s = scanner.nextLine();

        String rest = "keyence";
        int restI = 0;
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == rest.charAt(restI)) {
                restI++;
                if (restI == rest.length()) {
                    System.out.println("YES");
                    return;
                }
                continue;
            }

            if (s.substring(s.length() - (rest.length() - restI), s.length()).equals(rest.substring(restI, rest.length()))) {
                System.out.println("YES");
                return;
            } else {
                break;
            }
        }
        System.out.println("NO");
    }
}