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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>

int main(){
	int i,count=0,c=0,k[7];
	char s[101],ky[105]={'k','e','y','e','n','c','e',};
	scanf("%s",s);
	for(i=0;s[i]!=0;i++){
		if(s[i]==ky[count]){
			k[count]=i;
			count++;
		}
	}
	for(i=1;i<7;i++){
		if(k[i]-k[i-1]>1)c++;
	}
	if(count>=7&&c<=1){
		puts("YES");
	}else puts("NO");
	return 0;
}