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 Lua (5.3.2) (judge verdict: Accepted)

S=io.read()
s=string.lower(S)

if S:sub(1,1)=="A" then
    Counter=0
    for i=2, #S do
        if S:sub(i,i)=="C" and 3<=i and i<=#S-1 then
            Counter=Counter+1
        end
    end
    if Counter==1 then
        checker=0
        for i=1, #S do
            if S:sub(i,i)~=s:sub(i,i) then
                checker=checker+1
            end
        end
        if checker==2 then
            print("AC")
            return
        end
    end
end
print("WA")