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() {
    int i, j, len, index = 0;
    char *keyence = "keyence", S[100], tmp[100] = {'\0'};
    scanf("%s", S);
    len = strlen(S);
    for (i = 0; i < strlen(keyence); i++) {
        if (S[i] != keyence[i]) break;
    }
    for (j = i; j < strlen(keyence); j++) {
        tmp[index++] = keyence[j];
    }
    index = i;
    for (j = strlen(keyence) - i; j >= 1; j--) {
        if (S[len - j] != keyence[index++]) {
            printf("NO\n");
            return 0;
        }
    }
    printf("YES\n");
    return 0;
}