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.*;
import java.util.stream.*;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		String s = in.nextLine();
		if(s.charAt(0) != 'A') {
			System.out.println("WA");
			return;
		}
		if(s.length() < 4) {
			System.out.println("WA");
			return;
		}
		String tmp = s.substring(2, s.length()-1);
		// System.out.println(tmp);
		if(tmp.replaceAll("C", "").length() != tmp.length() - 1) {
			System.out.println("WA");
			return;
		}
		if(s.replaceAll("C", "").length() != s.length() - 1) {
			System.out.println("WA");
			return;
		}
		for(char ch : s.toCharArray()) {
			if(ch == 'A' || ch == 'C') {
				continue;
			}
			if(!Character.isLowerCase(ch)) {
				System.out.println("WA");
				return;
			}
		}
		System.out.println("AC");
	}
}