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++ (GCC 9.2.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>


using namespace std;

#define fastio() ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0)
#define ll long long
#define mk make_pair
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define sz(x) (int) (x).size()
#define print_vec(vec) for(int i=0;i<sz(vec);i++) cout << vec[i] << " ";
#define FORin(vec) for(int& x : vec) cin>>x;

void go(){
	string s;cin>>s;
	string ans="AC";
	if(s[0]!='A') {
		cout << "WA";
		return;
	}
	int c=0;
	for(int i=2;i<sz(s)-1;i++) {
		if(isupper(s[i])&&(s[i]!='A'&&s[i]!='C')) {
			ans="WA";
			break;
		}
		if(s[i]=='C') c++;
		if(c>1) {
			ans="WA";
			break;
		}
	}
	if(c==0) ans="WA";
	cout << ans;
}
int main(){
   
   fastio();
   cin.tie(0);
   cout.tie(0);

   go();

   return 0;
}