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 <string>
using namespace std;

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

    bool judge = true;
    if ( s.at(0) != 'A' ) judge = false;
    if ( s.find('C') != s.rfind('C') || !( s.find('C') >=2 && s.find('C') <= s.size()-2) ){
        judge = false;
    }
    int cnt = 0;
    for ( int i = 0 ; i < s.size(); i++ ){
        if ( islower(s.at(i))) cnt++;
    }
    if (cnt != s.size()-2 ) judge = false;

    string ans;
    if( judge ) ans = "AC";
    else ans = "WA";

    cout << ans << endl;
}