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: Accepted)

using System;

namespace ABC104B
{
    class Program
    {
        static void Main(string[] args)
        {
            var S = Console.ReadLine();


            Console.WriteLine(hoge(S));
        }

        static string hoge(string S)
        {
            if (!S.StartsWith("A"))
            {
                return "WA";
            }

            if (char.IsUpper(S[1]))
            {
                return "WA";
            }

            bool large = false;
            int max = S.Length - 1;
            for (int i = 2; i < max; ++i)
            {
                var v = S[i];
                if (char.IsUpper(v))
                {
                    if (!large)
                    {
                        if (v == 'C')
                        {
                            large = true;
                        } else
                        {
                            return "WA";
                        }
                    }
                    else
                    {
                        return "WA";
                    }
                }
            }

            if (!large || char.IsUpper(S[max]))
            {
                return "WA";
            }

            return "AC";
        }
    }
}