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: Wrong Answer)

import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);

		// 文字列の入力
		String s = sc.next();
    
		// 出力
		System.out.println(check(s) ? "AC" : "WA");
	}
    public static boolean check(String value) {
      String[] values = value.split("");
      if (!values[0].equals("A")) {
        return false;
      }
      int cIndex = -1;
      for(int i = 2; i < values.length - 2; i++) {
        if (values[i].equals("C")) {
          if (cIndex >= 0) {
            return false;
          } else {
            cIndex = i;
          }
        }
      }
      if (cIndex < 0) {
        return false;
      }
      for(int i = 1; i < value.length(); i++) {
        if (i == cIndex) {
          continue;
        }
        if (Character.isUpperCase(value.charAt(i))) {
          return false;
        }
      }
      return true;
    }
}