import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        }
        System.out.println(sb.toString());
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        }
        System.out.println(sb.toString());
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        }
        System.out.println(sb.toString());
    } main {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        }
        System.out.println(sb.toString());
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc StringBuilder sb = new StringBuilder(); sb new StringBuilder() for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        } int i = 0; int i = 0; i 0 i < s.length() i s.length() s.length s i++ i++ i {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        } {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        } if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            } s.charAt(i) == 'B' s.charAt(i) s.charAt s i 'B' {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } if (sb.length() > 0) sb.setLength(sb.length() - 1); sb.length() > 0 sb.length() sb.length sb 0 sb.setLength(sb.length() - 1) sb.setLength sb sb.length() - 1 sb.length() sb.length sb 1 {
                sb.append(s.charAt(i));
            } sb.append(s.charAt(i)) sb.append sb s.charAt(i) s.charAt s i 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 sc = new Scanner(System.in);
        String s = sc.next();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        }
        System.out.println(sb.toString());
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        }
        System.out.println(sb.toString());
    }
} Main
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'B') {
                if (sb.length() > 0) sb.setLength(sb.length() - 1);
            } else {
                sb.append(s.charAt(i));
            }
        }
        System.out.println(sb.toString());
    }
}
