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 <string>
#include <vector>

using namespace std;

int main(){
  string S; cin>>S;
  if(S[0]!='A'){cout<<"WA"<<endl; return 0; }
  int c=0,l=0;
  for(int i=2;i<(S.size()-1);i++){
    if(S[i]=='C') {c++; l=i;}
  }
  if(c!=1) { cout<<"WA"<<endl; return 0; }
  for(int i=1;i<S.size();i++){
    if((i!=l)&&(S[i]>='A')&&(S[i]<='Z')){
      cout<<"WA"<<endl;
      return 0;
    }
  }
  cout<<"AC"<<endl;

  return 0;
}