
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String[] s = scan.next().split("");
        scan.close();

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length; i++) {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        }

        System.out.println(sb.toString());
    }
} import java.util.Scanner; Scanner java.util public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String[] s = scan.next().split("");
        scan.close();

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length; i++) {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        }

        System.out.println(sb.toString());
    }
} Main public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String[] s = scan.next().split("");
        scan.close();

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length; i++) {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        }

        System.out.println(sb.toString());
    } main {
        Scanner scan = new Scanner(System.in);
        String[] s = scan.next().split("");
        scan.close();

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length; i++) {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        }

        System.out.println(sb.toString());
    } Scanner scan = new Scanner(System.in); scan new Scanner(System.in) String[] s = scan.next().split(""); s scan.next().split("") scan.next().split scan.next() scan.next scan "" scan.close() scan.close scan StringBuilder sb = new StringBuilder(); sb new StringBuilder() for (int i = 0; i < s.length; i++) {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        } int i = 0; int i = 0; i 0 i < s.length i s.length s s.length i++ i++ i {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        } {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        } if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            } s[i].equals("0") s[i].equals s[i] s i "0" {
                sb.append("0");
            } sb.append("0") sb.append sb "0" if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            } s[i].equals("1") s[i].equals s[i] s i "1" {
                sb.append("1");
            } sb.append("1") sb.append sb "1" {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            } if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                } sb.length() > 0 sb.length() sb.length sb 0 {
                    sb.deleteCharAt(sb.length() - 1);
                } sb.deleteCharAt(sb.length() - 1) sb.deleteCharAt sb sb.length() - 1 sb.length() sb.length sb 1 System.out.println(sb.toString()) System.out.println System.out System System.out sb.toString() sb.toString sb String[] args args public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String[] s = scan.next().split("");
        scan.close();

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length; i++) {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        }

        System.out.println(sb.toString());
    }
} public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String[] s = scan.next().split("");
        scan.close();

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length; i++) {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        }

        System.out.println(sb.toString());
    }
} Main

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String[] s = scan.next().split("");
        scan.close();

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length; i++) {
            if (s[i].equals("0")) {
                sb.append("0");
            } else if (s[i].equals("1")) {
                sb.append("1");
            } else {
                if (sb.length() > 0) {
                    sb.deleteCharAt(sb.length() - 1);
                }
            }
        }

        System.out.println(sb.toString());
    }
}
