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<cstdio>
#include<cstring>

using namespace std;

int cnt;
char str[1000001];

int main(){
	scanf("%s",str);
	if(str[0]!='A'){
		puts("WA");
		return 0;
	}
	int n=strlen(str);
	if(str[1]=='C'||str[n-1]=='C'){
		puts("WA");
		return 0;
	}
	for(int i=2;i<n-1;++i){
		if(str[i]=='C')++cnt;
		else if(str[i]>='B'&&str[i]<='Z'){
			puts("WA");
			return 0;
		}
	}
	if(cnt==1)puts("AC");else puts("WA");
}