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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<bits/stdc++.h>
using namespace std;
int main()
{
    string S; cin >> S;
    int cnt2 = 0;
    int Cpoint = -1;
    int judge = 0;
    for(int i = 2 ; i < S.size() - 1; i++)
    {
        if(S.at(i) == 'C')
        {
            if(Cpoint != -1) // Cが既に出ている場合は
            {
                Cpoint == -2; // Cpointに-2を代入しbreak
                break;
            }
            cnt2++;
            Cpoint = i;
        }
    }
    if(Cpoint != -2  && Cpoint != -1) //Cが一回出現した場合のみ実行
    {
        for(int i = 1; i < S.size(); i++)
        {
        
            if(isupper(S.at(i))) //Sのi番目が大文字なら実行
            {
                if(i == 1 || i == S.size() - 1 || S.at(i) !='C')  //Ｓが1番目か末尾で大文字ならWA、大文字がＣ以外でもWA
                {                                                 //ＳにＣが二つ以上ある場合や一回も出現していない場合は除外済み
                    judge = 1;           //judge = 1ならWAにする
                    break;
                }
            }
        }
    }
    if(S.at(0) == 'A' && cnt2 == 1 && judge == 0)
    {
        cout << "AC" << endl;
    }
    else
    {
        cout << "WA" << endl;
    }
}