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 Java (OpenJDK 11.0.6) (judge verdict: Accepted)

import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		// 整数の入力
		String a = sc.next();
        String s[] = a.split("");
        char[] c = a.toCharArray();
        int i;
        int count = 0;
        int check = 0;
        if(!s[0].equals("A")){
          System.out.println("WA");
          System.exit(0);
        }
        for(i = 1;i < a.length(); i++){
          if(Character.isUpperCase(c[i])) {
   			 count += 1;
		  }
          if(s[i].equals("C") && i > 1 && i < a.length() - 1){
             check += 1;
          }
        }
        if(count == 1 && check == 1){
          System.out.println("AC");
          System.exit(0);
        }
		
 		System.out.println("WA");
    }
}