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>
#define _GLIBCXX_DEBUG
#define rep(i,n) for (int i = 0; i < (int)(n); i++)
#define all(v) v.begin(),v.end()
#define INF INT_MAX;
typedef long long ll;
using namespace std;

int main(){
  string s; cin >> s;
  bool a = false,A=true;
  int c=0;
  rep(i,s.size()){
    if(i==0){
      if(s.at(i)=='A') a = true;
    }else if(i>1&&i<s.size()-1){
      if('a'>s.at(i)||'z'<s.at(i)){
        if(s.at(i)=='C') c++;
        else A = false;
      }
    }else{
      if('a'>s.at(i)||'z'<s.at(i)){
        A =false;
      }
    }
  }

  if(a&&A&&c==1) puts("AC");
  else puts("WA");
}