#include <bits/stdc++.h>
using namespace std;
string s;
int main()
{
	cin >> s;
	for (int i = 0; i < s.length(); i++)
	{
		if (s[i] == 'B') s[i - 1] = ' ';
		if (s[i] == 'B') s[i] = ' ';
	}
	for (int i = 0; i < s.length(); i++)
	{
		if (s[i] == ' ') continue;
		cout << s[i];
	}
	return 0;
}