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>


using namespace std;


int main()
{
	string S;
	int ns,ne;
	int cnt_c = 0;

	cin >> S;
	ns = 2;
	ne = S.size() - 2;

	if (S[0] != 'A') goto WA_END;

	for (int ni = 1; ni < S.size(); ni++) {
		if ('A' <= S[ni] && S[ni] <= 'Z') {
			if (S[ni] != 'C') {
				goto WA_END;
			}
			else {
				if (ni < ns || ne < ni) goto WA_END;
				if (cnt_c > 0) goto WA_END;
				cnt_c++;
			}
		}
	}
	if (cnt_c != 1) goto WA_END;

	printf("AC");
	return 0;

WA_END:
	printf("WA");

    return 0;
}