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 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <string.h>

typedef enum
{
	true = 1,
	false = 0
} bool;

void swap(int *xp, int *yp)
{
    int temp = *xp;
    *xp = *yp;
    *yp = temp;
}

void sort(int arr[], int n)
{
   int i, j;
   for (i = 0; i < n-1; i++)  
       for (j = 0; j < n-i-1; j++) 
           if (arr[j] > arr[j+1])
              swap(&arr[j], &arr[j+1]);
}

bool isupper(char a)
{
	if (a <= 'z' && a >= 'a') return false;
	return true;
}

int main()
{
	char a[100];
	scanf("%s", a);
	int n = strlen(a);
	bool oneC = false;
	if (a[0] != 'A') {puts("WA"); return 0;}
	for (int i = 1; i < n; i++)
	{
		if (isupper(a[i]))
		{
			if (a[i] == 'C' && !oneC)
			{
				oneC = true;
				if (i >= 2 && i <= n-2) continue;
				else {puts("WA"); return 0;}
			}
			else {puts("WA"); return 0;}
		}
	}
	puts("AC");	
	
	return 0;
}