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: Accepted)

#include <stdio.h>
#include <string.h>
int main()
{   char s1[20];
 while(scanf("%s",s1)!=EOF)
 {
  int t=0,s=0,i;

   int l=strlen(s1);
   for( i=1;i<l;i++)
   {
       if((i==1||i==l-1)&&s1[i]=='C')
            {   s=-1;
                break;
            }
         if(s1[i]=='C'&&i>=2&&i<=l-2)
                 t++;
        if(s1[i]=='B'||s1[i]=='A'||(s1[i]>='D'&&s1[i]<='Z'))
              {
                 s=-1;
                 break;
              }

   }
   if(s==-1)
    printf("WA\n");
   else if(s1[0]=='A'&&t==1)
    printf("AC\n");
    else
    printf("WA\n");

 }
    return 0;
}