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;

string a = {};

void input()
{
  cin >> a;
}

void solve()
{
  if(a[0] == 'A')
  {
    string sub = a.substr(2);
    int sum = 0;
    int index = 0;
    for(int i = 0; i < sub.length(); i++)
    {
      if(sub[i] == 'C')
      {
        index = i + 2;
        sum++;
      }
    }
    if(sum == 1)
    {
      string str = {};
      for(int i = 0; i < a.length(); i++)
      {
        if(i == 0 || i == index) continue;
        str += a[i];
      }
      bool t = true;
      for(auto c : str)
      {
        t &= islower(c);
      }
      if(t)
      {
        cout << "AC";
        return;
      }
    }
  }

  cout << "WA";
}

int main()
{
  input();
  solve();
  return 0;
}