// Arup Guha
// 4/15/2017
// Solution to 2017 NAIPC Problem J: Yin and Yang Stones

import java.util.*;
import java.io.*;

public class yinyangstones {

	public static void main(String[] args) throws Exception {

		BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
		String s = stdin.readLine().trim();

		// Count difference between white and black stones.
		int cnt = 0;
		for (int i=0; i<s.length(); i++) {
			if (s.charAt(i) == 'W')
				cnt++;
			else
				cnt--;
		}

		// This must be 0....
		if (cnt == 0)
			System.out.println(1);
		else
			System.out.println(0);
	}
}