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){
        string str = Console.ReadLine();
        char[] cha = new char[str.Length];
        for(int i=0;i<str.Length;i++){
            cha[i] = str[i];
        }
        int cCount = 0;
        int cNumber = 0;
        for(int i=2;i<cha.Length-2;i++){
            if(cha[i].ToString() == "C"){cCount++; cNumber = i;}
        }
        bool isLow = true;
        for(int i=1;i<cha.Length;i++){
            if(i==cNumber){
                continue;
            }
            if(cha[i].ToString().CompareTo(cha[i].ToString().ToLower()) != 0){
                isLow = false;
            }
        }
        if(cCount == 1 && isLow && cha[0].ToString() == "A"){
            Console.WriteLine("AC");
        }else{
            Console.WriteLine("WA");
            
        }
    }
}