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 C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;

string search(vector<char> ss) {
	for (int i(0); i < ss.size(); ++i) {
		vector<char> ssd = ss;
		for (int j = i; j < ssd.size(); ++j) {
			ssd.erase(ssd.begin() + i, ssd.begin() + j);
			string str(ssd.begin(), ssd.end());
			if (str == "keyence") {
				return "YES";
			}
			ssd = ss;
		}
	}
	return "NO";
}

int main() {
	ios::sync_with_stdio(false);
	string s; cin >> s;
	if (s == "keyence") {
		cout << "YES";
		return 0;
	}
	vector<char> ss(s.begin(), s.end());
	
	cout << search(ss);
	return 0;
}