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 Haskell (GHC 7.10.3) (judge verdict: Wrong Answer)

lcp [] _ = []
lcp _ [] = []
lcp (x:xs) (y:ys) = if x == y then x : lcp xs ys else []

lcs x y = reverse $ lcp (reverse x) (reverse y)

solve s
    | s == "keyence" = "YES"
    | otherwise      =
        let u = lcp s "keyence"
            v = lcs s "keyence"
        in if u ++ v == "keyence" then "YES" else "NO"

main = getLine >>= putStrLn . solve