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 Common Lisp (SBCL 1.1.14) (judge verdict: Wrong Answer)

(let ((count 0)
      (pre nil)
      (result (cons nil nil)))
  (dolist (x (coerce (read-line) 'list))
    (incf count)
    (cond ((and (= count 4) (eql x pre))
           (setf (car result) t))
          ((and (= count 6) (eql x pre))
           (setf (cdr result) t)))
    (setq pre x))
  (princ (if (and (null (car result)) (null (cdr result))) "No" "Yes")))