Problem:
Score : 100 points

Problem Statement

A string of length 6 consisting of lowercase English letters is said to be coffee-like if and only if its 3-rd and 4-th characters are equal and its 5-th and 6-th characters are also equal.

Given a string S, determine whether it is coffee-like.

Constraints

S is a string of length 6 consisting of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S

Output

If S is coffee-like, print Yes; otherwise, print No.

Sample Input 1

sippuu

Sample Output 1

Yes

In sippuu, the 3-rd and 4-th characters are equal, and the 5-th and 6-th characters are also equal.

Sample Input 2

iphone

Sample Output 2

No

Sample Input 3

coffee

Sample Output 3

Yes

Solution in Haskell (GHC 7.10.3) (judge verdict: Accepted)

main :: IO()
main = do
    n <- getLine 
    putStrLn $ if isCoffee n then "Yes" else "No"

isCoffee :: String -> Bool
isCoffee s =
    let
        c3 = s !! 2 
        c4 = s !! 3
        c5 = s !! 4
        c6 = s !! 5 
    in
    c3 == c4 && c5 == c6