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: Wrong Answer)

#include <iostream>
#include <map>
#include <algorithm>
#include <string>
#include <vector> 
#include <numeric>
#include <cmath>
#include <queue>
#include <iomanip>
#include <functional>


#define CHMAX(a,b) a = std::max(a,b)
#define CHMIN(a,b) a = std::min(a,b)
#define CHABS(a) a = std::abs(a) 
#define COUT(a) std::cout << a << std::endl
#define CERR(a) std::cerr << a << std::endl
#define FOR(n) for(lli i = 0; i < n; i++)

using namespace std;
using lli = long long int;
using pll = pair<lli, lli>;
using tlll = tuple<lli, lli, lli>;
using vll = vector<lli>;

lli mod197 = 1000000007LL;
lli INF = 10000000000000;

// ax + by = gcd(a,b) 最大公約数
template< typename T >
T extgcd(T a, T b, T& x, T& y) {
	T d = a;
	if (b != 0) {
		d = extgcd(b, a % b, y, x);
		y -= (a / b) * x;
	}
	else {
		x = 1;
		y = 0;
	}
	return d;
}


bool solve(string s) {

	if (s[0] == 'A' && std::toupper(s[1]) != s[1]) {

		string t = s.substr(2, s.size() - 2);

		int count = 0;
		for (int i = 0; i < t.size(); i++) {
			if (std::toupper(t[i]) == t[i]) {
				count++;
				if (t[i] != 'C') {
					return false;
				}
			}
		}

		if (count == 1) {
			return true;
		}
	}

	return false;
}

int main(void) {
	
	string s;
	cin >> s;

	if (solve(s)) {
		cout << "AC" << endl;
	}
	else {
		cout << "WA" << endl;
	}

	return 0;
}