import java.util.Scanner;

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

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

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

		StringBuilder sb = new StringBuilder();
		for (int i = 0; i < s.length; i++) {
			if (s[i] == 'B') {
				if (sb.length() > 0) {
					sb.deleteCharAt(sb.length() - 1);
				}
			} else {
				sb.append(s[i]);
			}
		}
		System.out.println(sb.toString());
	} main {
		Scanner sc = new Scanner(System.in);
		char[] s = sc.next().toCharArray();
		sc.close();

		StringBuilder sb = new StringBuilder();
		for (int i = 0; i < s.length; i++) {
			if (s[i] == 'B') {
				if (sb.length() > 0) {
					sb.deleteCharAt(sb.length() - 1);
				}
			} else {
				sb.append(s[i]);
			}
		}
		System.out.println(sb.toString());
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) char[] s = sc.next().toCharArray(); s sc.next().toCharArray() sc.next().toCharArray sc.next() sc.next sc sc.close() sc.close sc StringBuilder sb = new StringBuilder(); sb new StringBuilder() for (int i = 0; i < s.length; i++) {
			if (s[i] == 'B') {
				if (sb.length() > 0) {
					sb.deleteCharAt(sb.length() - 1);
				}
			} else {
				sb.append(s[i]);
			}
		} int i = 0; int i = 0; i 0 i < s.length i s.length s s.length i++ i++ i {
			if (s[i] == 'B') {
				if (sb.length() > 0) {
					sb.deleteCharAt(sb.length() - 1);
				}
			} else {
				sb.append(s[i]);
			}
		} {
			if (s[i] == 'B') {
				if (sb.length() > 0) {
					sb.deleteCharAt(sb.length() - 1);
				}
			} else {
				sb.append(s[i]);
			}
		} if (s[i] == 'B') {
				if (sb.length() > 0) {
					sb.deleteCharAt(sb.length() - 1);
				}
			} else {
				sb.append(s[i]);
			} s[i] == 'B' s[i] s i 'B' {
				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 {
				sb.append(s[i]);
			} sb.append(s[i]) sb.append sb s[i] 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) throws Exception {
		Scanner sc = new Scanner(System.in);
		char[] s = sc.next().toCharArray();
		sc.close();

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

		StringBuilder sb = new StringBuilder();
		for (int i = 0; i < s.length; i++) {
			if (s[i] == 'B') {
				if (sb.length() > 0) {
					sb.deleteCharAt(sb.length() - 1);
				}
			} else {
				sb.append(s[i]);
			}
		}
		System.out.println(sb.toString());
	}
} Main
import java.util.Scanner;

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

		StringBuilder sb = new StringBuilder();
		for (int i = 0; i < s.length; i++) {
			if (s[i] == 'B') {
				if (sb.length() > 0) {
					sb.deleteCharAt(sb.length() - 1);
				}
			} else {
				sb.append(s[i]);
			}
		}
		System.out.println(sb.toString());
	}
}
