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: Accepted)

#include<stdio.h>
#include<string.h>
int main()
{
    char s[102];
    scanf("%s", s);
    int i, j;
    char t[8] = "keyence";
    i = j = 0;
    while (s[i] == t[j] && i < strlen(s))
    {
        i++;
        j++;
    }
    i = strlen(s) - 7 + j;
    while (s[i] == t[j] && i < strlen(s))
    {
        i++;
        j++;
    }
    if (i == strlen(s))
        printf("YES\n");
    else
        printf("NO\n");
    return 0;
}