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 PHP7 (7.0.15) (judge verdict: Wrong Answer)

<?php
$s = trim(fgets(STDIN));

$f = true;

if ($s[0] !== 'A') {
    $f = false;
}

$C = 0;
$sss = 'ABDEFGHIJKLMNOPQRSTUVWXYZ';
for ($i = 2; $i < strlen($s) - 1; $i++) {
    if ($s[$i] == 'C') {
        $C++;
    }
    if (strpos($sss, $s[$i])) {
        $f = false;
    }
}
if ($C !== 1) {
    $f = false;
}

if ($f) {
    echo 'AC' . PHP_EOL;
} else {
    echo 'WA' . PHP_EOL;
}