import java.util.Deque;

import java.util.HashMap;

import java.util.LinkedList;

import java.util.Map;

import java.util.Scanner;

public class Solution {

Map<Integer,Integer> map ;

Deque<Integer> dq;

int capacity;

public Solution(int capacity) {

map = new HashMap<Integer,Integer>();

dq = new LinkedList<Integer>();

this.capacity = capacity;

}

public int get(int key) {

if(map.containsKey(key))

return map.get(key);

return -1;

}

public void set(int key, int value) {

if(!map.containsKey(key))

{

if(dq.size()==capacity)

{

dq.remove(key);

map.remove(key);

}

}

else

{

map.remove(dq.removeLast());

}

dq.addFirst(key);

map.put(key, value);

}

public static void main(String[] args)

{

Scanner s = new Scanner(System.in);

int n = s.nextInt();

Solution solution = new Solution( n );

for(int i=0;i<n;i++)

{

int key = s.nextInt();

int value = s.nextInt();

solution.set( key, value );

}

System.out.println( solution.get( 6 ) );

System.out.println( solution.get( 5 ) );

System.out.println( solution.get( 1 ) );

System.out.println( solution.get( 2 ) );

}

}