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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		boolean possible = true;

		if (!(s.charAt(0) == 'A')) {
			possible = false;
		} else if (s.substring(2, s.length() - 1).indexOf("C") == -1) {
			possible = false;
		} else {
			String tmpS =  s.substring(1, s.substring(2, s.length() - 1).indexOf("C") + 2) + s.substring(s.substring(2, s.length() - 1).indexOf("C") + 3);
			if (!tmpS.toUpperCase().toLowerCase().equals(tmpS)) possible = false;
		}
		if (possible) {
			System.out.println("AC");
		} else {
			System.out.println("WA");
		}
	}
}