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 Python (3.4.3) (judge verdict: Wrong Answer)

import sys
ans = False
ans_str = {True:'YES', False:'NO'}
# 7 chars
target = 'keyence'

input_str = input()
input_len = len(input_str)
if target in input_str:
    if input_str.index(target) == 0:
        print('YES')
    elif input_str.index(target) == -7:
        print('YES')
    else:
        print('NO')
    sys.exit()
else:
    for i in range(6):
        if input_str.find(target[:(i+1)]) == 0 and input_str.find(target[(i+1):]) == input_len-(6-i) and input_len > 7:
            print('YES')
            sys.exit()
    print('NO')
    sys.exit()