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 scanner = new Scanner(System.in);
		String S = scanner.nextLine();
		scanner.close();

		int count = 0;
		for (int n = 0; n < S.length(); n++) {
			String c = S.substring(n, n + 1);

			if (n == 0) {
				if (!c.equals("A")) {
					System.out.println("WA");
					return;
				}
				continue;
			}

			if (n == 1 || n == S.length() - 1) {
				if (!c.equals("A") && Character.isUpperCase(S.charAt(n))) {
					System.out.println("WA");
					return;
				}
				continue;
			}

			if (c.equals("C") && count == 0) {
				count++;
				continue;
			}

			if (Character.isUpperCase(S.charAt(n))) {
				System.out.println("WA");
				return;
			}
		}
		if (count == 0) {
			System.out.println("WA");
			return;
		}
		System.out.println("AC");
	}
}