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<time.h>
#include<iostream>
#include<string>
#include<algorithm>
#include<vector>
#include<iomanip>
#include<math.h>
#include<complex>
#include<queue>
#include<deque>
#include<stack>
#include<map>
#include<set>
#include<bitset>
#include<functional>
#include<assert.h>
#include<numeric>
using namespace std;
#define REP(i,m,n) for(int i=(int)(m) ; i < (int) (n) ; ++i )
#define rep(i,n) REP(i,0,n)
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
using ll = long long;
using vi = vector<int>;
using vvi = vector<vector<int>>;
using vll = vector<ll>;
using vvll = vector<vector<ll>>;
const int inf=1e9+7;
const ll longinf=1LL<<60 ;
const ll mod=1e9+7 ;
using namespace std;
struct Fast { Fast(){ std::cin.tie(0); ios::sync_with_stdio(false); } } fast;

template<typename ...Ts>
void show(Ts... ts){
  cout<<"#:";
  auto print=[](auto v){cout<<v<<" ";};
  initializer_list<int>{(void(print(ts)),0)...};
  cout<<endl;
}

int main(void){
    int n;
    string s;
    cin>>s;
    n=s.size();
    bool fl=false;
    string ans="AC";
    if (s[0]!='A')ans="WA";
    REP(i,2,n){
        if (s[i]=='C'){
            if (fl==true or i==n-1){
                ans="WA";
            }else{
                fl=true;
            }
        }else{
            if('a'<=s[i] and s[i]<='z'){
                0;
            }else{
                ans="WA";
            }
        }
    }
    if (fl==false or s[1]<'a' or 'z'<s[1]){
        ans="WA";
    }
    cout<<ans;
}