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>
#include <ctype.h>

int main(void)
{
  char S[11];
  int pos;
  int cnt=0, flg, len, i, j=0;

  scanf("%s", S);
  len = strlen(S);
  pos = (int)(strstr(S, "C") - S) + 1;
  if(pos==len || pos<3){ puts("WA"); return 0;}
  if(S[0]=='A')
  {
    for(i=0; i<len; i++)
    {
        if(S[i]=='C'){cnt++;}
        if(islower(S[i])){j++;}
    }
  }
  if(j != (len-2)){ puts("WA"); return 0;}
  puts("AC");
  return 0;
}