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();

		String ans = "AC";

		int c = 0;
		for (int i = 2; i < S.length() - 1; i++) {
			if (S.substring(i, i + 1).equals("C")) {
				c++;
			} else if (Character.isUpperCase(S.charAt(i))) {
				c = 2;
			}
		}

		if (Character.isUpperCase(S.charAt(1)) || Character.isUpperCase(S.charAt(S.length() - 1))
				|| !S.substring(0, 1).equals("A")
				|| S.substring(1, 2).equals("C")
				|| S.substring(S.length() - 1, S.length()).equals("C") || c != 1) {
			ans = "WA";
		}

		System.out.println(ans);
		sc.close();
	}

}