import java.util.Scanner;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String str = sc.nextLine();
    StringBuilder ans = new StringBuilder("");
    for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(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 str = sc.nextLine();
    StringBuilder ans = new StringBuilder("");
    for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    }
    System.out.println(ans);
  }
} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String str = sc.nextLine();
    StringBuilder ans = new StringBuilder("");
    for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    }
    System.out.println(ans);
  } main {
    Scanner sc = new Scanner(System.in);
    String str = sc.nextLine();
    StringBuilder ans = new StringBuilder("");
    for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    }
    System.out.println(ans);
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String str = sc.nextLine(); str sc.nextLine() sc.nextLine sc StringBuilder ans = new StringBuilder(""); ans new StringBuilder("") for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    } int i = 0; int i = 0; i 0 i < str.length() i str.length() str.length str i++ i++ i {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    } {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    } char ch = str.charAt(i); ch str.charAt(i) str.charAt str i switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      } ch case '0': '0' case '0': case '1': '1' case '1': ans.append(ch) ans.append ans ch break; case 'B': 'B' case 'B': if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          } ans.length() != 0 ans.length() ans.length ans 0 {
            ans.deleteCharAt(ans.length() - 1);
          } ans.deleteCharAt(ans.length() - 1) ans.deleteCharAt ans 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 str = sc.nextLine();
    StringBuilder ans = new StringBuilder("");
    for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    }
    System.out.println(ans);
  }
} public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String str = sc.nextLine();
    StringBuilder ans = new StringBuilder("");
    for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(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 str = sc.nextLine();
    StringBuilder ans = new StringBuilder("");
    for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    }
    System.out.println(ans);
  }
}
