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 <bits/stdc++.h>

using namespace std;
int main()
{
    string s;
    cin >> s;
    if(s[0] != 'A'){
        cout << "WA" << endl;
        return 0;
    }
    int c = 0;
    int n = -1;
    for(int i = 2; i <= s.size()-2; i++){
        if(s[i] == 'C'){
            c++;
            n = i;
        }
    }
    if(c != 1){
        cout << "WA" << endl;
        return 0;
    }
    for(int i = 1; i < s.size(); i++){
        if(i != n && s[i] < 'a'){
            cout << "WA" << endl;
            return 0;
        }
    }

    cout << "AC" << endl;

    return 0;
}