import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String s = scan.next();
        char[] cs = s.toCharArray();

        String ans = "";
        for (int i = 0; i < cs.length; i++) {
            if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            }
        }
        System.out.println(ans);
    }
} 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();
        char[] cs = s.toCharArray();

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

        String ans = "";
        for (int i = 0; i < cs.length; i++) {
            if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            }
        }
        System.out.println(ans);
    } main {
        Scanner scan = new Scanner(System.in);
        String s = scan.next();
        char[] cs = s.toCharArray();

        String ans = "";
        for (int i = 0; i < cs.length; i++) {
            if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            }
        }
        System.out.println(ans);
    } Scanner scan = new Scanner(System.in); scan new Scanner(System.in) String s = scan.next(); s scan.next() scan.next scan char[] cs = s.toCharArray(); cs s.toCharArray() s.toCharArray s String ans = ""; ans "" for (int i = 0; i < cs.length; i++) {
            if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            }
        } int i = 0; int i = 0; i 0 i < cs.length i cs.length cs cs.length i++ i++ i {
            if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            }
        } {
            if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            }
        } if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            } cs[i] == 'B' cs[i] cs i 'B' {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } 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 ans.substring(0, ans.length() - 1) ans.substring ans 0 ans.length() - 1 ans.length() ans.length ans 1 {
                ans += cs[i];
            } ans += cs[i] ans cs[i] cs i 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 scan = new Scanner(System.in);
        String s = scan.next();
        char[] cs = s.toCharArray();

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

        String ans = "";
        for (int i = 0; i < cs.length; i++) {
            if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            }
        }
        System.out.println(ans);
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String s = scan.next();
        char[] cs = s.toCharArray();

        String ans = "";
        for (int i = 0; i < cs.length; i++) {
            if (cs[i] == 'B') {
                if (ans.length() != 0) {
                    ans = ans.substring(0, ans.length() - 1);
                }
            } else {
                ans += cs[i];
            }
        }
        System.out.println(ans);
    }
}
