import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		sc.close();
		
		String ans = "";
		for(int i = 0;i < s.length();++i) {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		}
		System.out.println(ans);
	}
} import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		sc.close();
		
		String ans = "";
		for(int i = 0;i < s.length();++i) {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		}
		System.out.println(ans);
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		sc.close();
		
		String ans = "";
		for(int i = 0;i < s.length();++i) {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		}
		System.out.println(ans);
	} main {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		sc.close();
		
		String ans = "";
		for(int i = 0;i < s.length();++i) {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		}
		System.out.println(ans);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc sc.close() sc.close sc String ans = ""; ans "" for(int i = 0;i < s.length();++i) {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		} int i = 0; int i = 0; i 0 i < s.length() i s.length() s.length s ++i ++i i {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		} {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		} switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			} s.charAt(i) s.charAt s i case '0': '0' case '0': case '1': '1' case '1': ans = ans + s.charAt(i) ans ans + s.charAt(i) ans s.charAt(i) s.charAt s i break; case 'B': 'B' case 'B': if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1); ans.length() > 0 ans.length() ans.length ans 0 ans = ans.substring(0, ans.length()-1) ans ans.substring(0, ans.length()-1) ans.substring ans 0 ans.length()-1 ans.length() ans.length ans 1 break; System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		sc.close();
		
		String ans = "";
		for(int i = 0;i < s.length();++i) {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		}
		System.out.println(ans);
	}
} public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		sc.close();
		
		String ans = "";
		for(int i = 0;i < s.length();++i) {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		}
		System.out.println(ans);
	}
} Main
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		sc.close();
		
		String ans = "";
		for(int i = 0;i < s.length();++i) {
			switch(s.charAt(i)) {
			case '0':
			case '1':
				ans = ans + s.charAt(i);
				break;
			case 'B':
				if(ans.length() > 0)
					ans = ans.substring(0, ans.length()-1);
				break;
			}
		}
		System.out.println(ans);
	}
}
