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;

class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        int size = str.length();

        if("A".equals(str.substring(0,1))){
            int num =0;
            String str2 = str.substring(2,size-1);
            int size2 = str2.length();
            for(int i=0;i<size2;i++){
                String str4 = str2.substring(0,1);
                if(str4.equals("C")){
                    num = num+1;
                }
                str2 = str2.substring(1);
            }
            if(num==1){
                str2 = str.substring(2,size-1);
                str2 = str2.replace("C","c");
                str2 = str2.concat(str.substring(str.length() -1));
                str2 = str.substring(1,2).concat(str2);
                String str3 = str2.toLowerCase();

                if(str2.equals(str3)){
                    System.out.println("AC");
                }else{
                    System.out.println("WA"); 
                }

            }else{
                System.out.println("WA");    
            }
        }else{
            System.out.println("WA");
        }
    }
}