#include <iostream>
#include "stack.h"
#include <fstream>

ifstream in("input.txt");
ofstream out("output.txt");

int main(){
	Stack<int> input;
	Stack<int> output;
	int n, tmp = 0;
	in >> n;

	for (int i = 0; i < n; i++){
		in >> tmp;
		input.Push(tmp);
	}

	bool set = true;
	while (!input.Empty()){
		if (input.Top() != tmp || set){
			tmp = input.Top();
			output.Push(tmp);
			set = false;
		}
		input.Pop();
	}
	while (!output.Empty()){
		out << output.Top() << " ";
		output.Pop();
	}

	out << endl;
	in.close();
	out.close();
	return 0;

}