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: Wrong Answer)

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

int main(){
	string s;
	cin >> s;
	string key = "keyence";
	int i, j;
	int cnt = 0;
	for(i = 0, j = 0; i < (int)s.size() && j < (int)key.size(); i++) {
		if(s[i] == key[j]) {
			j++;
		}else{
			cnt++;
		}
	}
	if(cnt == (int)(s.size() - key.size()) && i == (int)s.size() && j == (int)key.size()) printf("YES\n");
	else printf("NO\n");
}