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.io.BufferedReader;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Map;
import java.util.Map.Entry;

import java.util.PriorityQueue;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.TreeSet;

public class Main {

	public static class UnionFind {
		int[] par; //

		public UnionFind(int n) {
			par = new int[n];
			for(int i = 0; i < n; i++){
				par[i] = -1;
			}
		}

		public int find(int x) {
			if(par[x] < 0){
				return x;
			}else{
				return par[x] = find(par[x]);
			}
		}

		public boolean union(int x, int y) {
			x = find(x);
			y = find(y);

			if(x != y){
				if(par[y] < par[x]){ // 多い方が根になるようにスワップする.
					int tmp = x;
					x = y;
					y = tmp;
				}
				par[x] += par[y];
				par[y] = x;
				return true;
			}else{
				return false;
			}
		}

		public boolean same(int x, int y) {
			return find(x) == find(y);
		}

		public int size(int x) {
			return -par[find(x)];
		}
	}
	
	public static int[][] move_dirs = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}};

	public static void main(String[] args) throws IOException {
		try(final Scanner sc = new Scanner(System.in)){
			final String pat =  "keyence";
			final String str = sc.next();
			
			for(int i = 0; i <= pat.length(); i++) {
				final String exp = "^" + pat.substring(0, i) + ".*" + pat.substring(i) + "$";
				
				if(str.matches(exp)) {
					System.out.println("YES");
					return;
				}
			}
			
			System.out.println("NO");
		}
	}

	public static class Scanner implements Closeable {
		private BufferedReader br;
		private StringTokenizer tok;

		public Scanner(InputStream is) throws IOException {
			br = new BufferedReader(new InputStreamReader(is));
		}

		private void getLine() throws IOException {
			while(!hasNext()){
				tok = new StringTokenizer(br.readLine());
			}
		}

		private boolean hasNext() {
			return tok != null && tok.hasMoreTokens();
		}

		public String next() throws IOException {
			getLine();
			return tok.nextToken();
		}

		public int nextInt() throws IOException {
			return Integer.parseInt(next());
		}

		public long nextLong() throws IOException {
			return Long.parseLong(next());
		}

		public double nextDouble() throws IOException {
			return Double.parseDouble(next());
		}

		public int[] nextIntArray(int n) throws IOException {
			final int[] ret = new int[n];
			for(int i = 0; i < n; i++){
				ret[i] = this.nextInt();
			}
			return ret;
		}

		public long[] nextLongArray(int n) throws IOException {
			final long[] ret = new long[n];
			for(int i = 0; i < n; i++){
				ret[i] = this.nextLong();
			}
			return ret;
		}

		public void close() throws IOException {
			br.close();
		}
	}
}