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 C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
class Program
{
	static void Main(string[] args)
	{
		// 整数の入力
		int c=0;
		string i = Console.ReadLine();
		string output="AC";
        if(i.Substring(0, 1)!="A")output="WA";
        else{
            int nagasa=i.Length;
            string a=i.Substring(2,nagasa-3);
            if(CountChar(a, 'C')!=1)output="WA";
            else{
                
                char po='a';
                //Console.WriteLine(po);
                for(int f=0;f<26;f++){
                    Console.WriteLine(po);
                    c+=CountChar(i, po);
                    po++;
                }
                if(po!=nagasa-2)output="WA";
            }
        }
        
		//出力
		Console.WriteLine(output);
	}
	public static int CountChar(string s, char c) 
  {
    return s.Length - s.Replace(c.ToString(), "").Length;
  }
}