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 Python (3.4.3) (judge verdict: Accepted)

import re
import sys

def check_upper_char(string):
    result = re.search('[A-Z]', string)
    return True if result else False

def in_onec(s):
    cnt = 0
    for i in range(len(s)):
        if s[i] == 'C':
            cnt += 1

    if cnt == 1:
        return True
    else:
        return False

s = input()

sub_s = s[2:-1]

if (s[0] == 'A') and in_onec(sub_s):
    s = s.replace('A', '')
    s = s.replace('C', '')
    if not check_upper_char(s):
        print('AC')
        sys.exit()
print('WA')