import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    char[] s_char = sc.next().toCharArray();
    String ans = "";
    for (int i = 0; i < s_char.length; i++) {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    }
    System.out.println(ans);
  }
} import java.util.*; util.* java public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    char[] s_char = sc.next().toCharArray();
    String ans = "";
    for (int i = 0; i < s_char.length; i++) {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    }
    System.out.println(ans);
  }
} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    char[] s_char = sc.next().toCharArray();
    String ans = "";
    for (int i = 0; i < s_char.length; i++) {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    }
    System.out.println(ans);
  } main {
    Scanner sc = new Scanner(System.in);
    char[] s_char = sc.next().toCharArray();
    String ans = "";
    for (int i = 0; i < s_char.length; i++) {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    }
    System.out.println(ans);
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) char[] s_char = sc.next().toCharArray(); s_char sc.next().toCharArray() sc.next().toCharArray sc.next() sc.next sc String ans = ""; ans "" for (int i = 0; i < s_char.length; i++) {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    } int i = 0; int i = 0; i 0 i < s_char.length i s_char.length s_char s_char.length i++ i++ i {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    } {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    } if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      } s_char[i] == '0' s_char[i] s_char i '0' {
        ans += "0";
      } ans += "0" ans "0" if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      } s_char[i] == '1' s_char[i] s_char i '1' {
        ans += "1";
      } ans += "1" ans "1" if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      } s_char[i] == 'B' && ans.length() > 0 s_char[i] == 'B' s_char[i] s_char i 'B' ans.length() > 0 ans.length() ans.length ans 0 {
        ans = ans.substring(0, ans.length() - 1);
      } 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 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);
    char[] s_char = sc.next().toCharArray();
    String ans = "";
    for (int i = 0; i < s_char.length; i++) {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    }
    System.out.println(ans);
  }
} public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    char[] s_char = sc.next().toCharArray();
    String ans = "";
    for (int i = 0; i < s_char.length; i++) {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    }
    System.out.println(ans);
  }
} Main
import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    char[] s_char = sc.next().toCharArray();
    String ans = "";
    for (int i = 0; i < s_char.length; i++) {
      if (s_char[i] == '0') {
        ans += "0";
      } else if (s_char[i] == '1') {
        ans += "1";
      } else if (s_char[i] == 'B' && ans.length() > 0) {
        ans = ans.substring(0, ans.length() - 1);
      }
    }
    System.out.println(ans);
  }
}