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>

int main(void){
  char S[11];
  char check;
  int check_c=-1;
  int i;
  int len=0;
  scanf("%s", S);
  check = S[len];
  while(check != '\0'){
    len++;
    check = S[len];
  }

  check = S[0];
  S[0] = 'a';
  if(check != 'A'){
    printf("WA\n");
    return 0;
  }
  for(i=2;i<=len-5;i++){
    if(S[i] == 'C'){
      check_c = i;
      S[i] = 'a';
      break;
    }
  }

  if(check_c == -1){
    printf("WA\n");
    return 0;
  }
  for(i=0;i<=len-1;i++){
    if(S[i] < 97 || S[i] > 122){
      printf("WA\n");
      return 0;
    }
  }
  printf("AC\n");
  return 0;
}