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: Runtime Error)

#include <stdio.h>
#include <stdlib.h>

int main()
{
  char S[10]={};
  int i,k;
  scanf("%s",&S);
  while(S[i]!='\0')
    i++;
  if(S[0]!='A')
    {
    printf("WA\n");
    exit(1);
    }
  else if(S[2]=='C'&&S[i-2]=='C')
    {
    printf("WA\n");
    exit(1);
    }
  else if(S[2]!='C'&&S[i-2]!='C')
    {
    printf("WA\n");
    exit(1);
    }
  for(k=0; k<i; k++)
    {
      if(S[k]!='A'&&S[k]!='C')
        {
          if(S[k]>=65&&S[k]<=90)
            {
            printf("WA\n");
            exit(1);
            }
        }
    }
  printf("AC\n");
  return 0;
}