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: Accepted)

#include <iostream>
#include <vector>
#include <algorithm>
#include <stdio.h>
#include <math.h>
#include <string>
#include <cctype>

using namespace std;

const int mod = 1000000007;
#define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))

int main()
{
    string s;
    cin >> s;

    if (s[0] != 'A')
    {
        printf("WA");
        return 0;
    }

    int count = 0;
    int index = -1;
    for (int i = 2; i < s.size()-1; i++)
    {
       if (s[i] == 'C')
       {
           count++;
           index = i;
       }
    }
    
    if (count != 1)
    {
        printf("WA");
        return 0;
    }

    for (int i = 0; i < s.size(); i++)
    {
        if (i == 0 || i == index)
        {
            continue;
        }
        
        if (isupper(s[i]))
        {
            printf("WA");
            return 0;
        }  
    }
    
    printf("AC");
    return 0;
}