백준 12904번 : A와 B

import java.io.*;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        String s = br.readLine();
        StringBuilder t = new StringBuilder(br.readLine());

        int n = 0;
        while (t.length() != 0 && n == 0) {
            if (t.lastIndexOf("A") == t.length()  - 1) {
                t.deleteCharAt(t.lastIndexOf("A"));
            } else {
                t.deleteCharAt(t.lastIndexOf("B"));
                t = t.reverse();
            }
            n = s.contentEquals(t) ? 1 : 0;
        }
        System.out.println(n);
    }
}