Problem:
Score : 200 points

Problem Statement

You are given a string S. Each character of S is uppercase or lowercase English letter.
Determine if S satisfies all of the following conditions:

The initial character of S is an uppercase A.

There is exactly one occurrence of C between the third character from the beginning and the second to last character (inclusive).

All letters except the A and C mentioned above are lowercase.

Constraints

4 ≤ |S| ≤ 10 (|S| is the length of the string S.)

Each character of S is uppercase or lowercase English letter.

Input

Input is given from Standard Input in the following format:

S

Output

If S satisfies all of the conditions in the problem statement, print AC; otherwise, print WA.

Sample Input 1

AtCoder

Sample Output 1

AC

The first letter is A, the third letter is C and the remaining letters are all lowercase, so all the conditions are satisfied.

Sample Input 2

ACoder

Sample Output 2

WA

The second letter should not be C.

Sample Input 3

AcycliC

Sample Output 3

WA

The last letter should not be C, either.

Sample Input 4

AtCoCo

Sample Output 4

WA

There should not be two or more occurrences of C.

Sample Input 5

Atcoder

Sample Output 5

WA

The number of C should not be zero, either.

Solution in Common Lisp (SBCL 2.0.3) (judge verdict: Accepted)

(let* ((l (concatenate 'list (read-line)))
       (check-c-list (reverse (cdr (reverse (cddr l)))))
       (check-lowercase-list (remove #\C check-c-list)))
  (format t "~A~%"
          (if (and (= (count #\C check-c-list) 1)
                   (every #'lower-case-p check-lowercase-list)
                   (char= (car l) #\A)
                   (lower-case-p (cadr l))
                   (lower-case-p (car (last l))))
            'ac
            'wa)))