import java.util.BitSet;
import java.util.Scanner;

public class Main {

public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int total = sc.nextInt();
    BitSet set = new BitSet(total);
    for (int i=0; i < total; i++) {
        int num = sc.nextInt();
        set.set(num);
    }
    for (int i=0; i<set.size(); i++) {
        if (set.get(i)) {
            System.out.println(i);
        }
    }
}

}