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>
int main(void){
    // Your code here!
    char s[1000];
    int n, a=0, b=0, i;
    
    scanf("%s",s);
    n=strlen(s);
    
    if(s[0]!='A'){
        printf("WA\n");
        return 0;
    }
    
    for(i=2;i<n-2;i++){
            if(s[i]=='C') a++;
        }
    if(a!=1){
        printf("WA\n");
        return 0;    
    }
     
    for(i=0;i<n;i++){
        if((s[i]<'a')||(s[i]>'z')) b++;
    }
    if(b!=2){
        printf("WA\n");
        return 0;
    }
    
    printf("AC\n");
    return 0;
}