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 9.2.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <string.h>

int main (void)
{
    int k=0,key=0;
    char s[101],st[8];
    char t[8]="keyence";
    scanf("%s",s);
    for(int i=0;i<strlen(s)&&k<8;i++)
    {
        if(s[i]==t[k])
        {
            st[k++]=s[i];
            if(key==1)
            {
                key=2;
            }
        }else{
            if(key==2)
            {
                key=3;
                break;
            }
            key=1;
        }
    }
    if(strcmp(st,t)==0&&key!=3)
    {
        puts("YES");
    }else{
        puts("NO");
    }
    return 0;
}