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 Java7 (OpenJDK 1.7.0) (judge verdict: Accepted)

import java.util.*;
import java.io.*;

class Main {
  public static void main(String[] args) throws Exception{
    try (Scanner sc = new Scanner(System.in)){
      String S = sc.next();
      if (S.charAt(0) != 'A'){
        System.out.println("WA");
        return;
      }
      String sub = S.substring(2, S.length()-1);
      int count = 0;
      for (int i = 0; i < sub.length(); i++) {
        if (sub.charAt(i) == 'C') count++;
      }
      if (count != 1) {
        System.out.println("WA");
        return;
      }
      S = S.replace("A", "");
      S = S.replace("C", "");
      for (int i = 0; i < S.length(); i++) {
        if (Character.isUpperCase(S.charAt(i))) {
          System.out.println("WA");
          return;
        }
      }
      System.out.println("AC");
    }
  }
}