// n m
// 1 1
// 2 2
// 3 3
// 4 4
// 4 4
import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int n = sc.nextInt(); // n
int m = sc.nextInt(); // m
HashMap map = new HashMap<>();
for (int i = 0; i < n; i++) {
int id = sc.nextInt();
int score = sc.nextInt();
if (map.containsKey(id)) {
map.put(id, map.get(id) + score);
} else {
map.put(id, score);
}
}
List> list = new ArrayList<>(map.entrySet());
// 按照value排åº
Collections.sort(list, (o1, o2) -> {
return o2.getValue() - o1.getValue();
});
for (int i = 0; i < m; i++) {
System.out.println(list.get(i).getKey());
}
}
}
class TreeNode {
int val;
TreeNode left;
TreeNode right;
TreeNode(int x){val = x;}
}
class ListNode {
int val;
ListNode next;
public ListNode(int val) {
this.val = val;
}
}
class ListNodeTools {
public static ListNode getListNode(int[] nums) {
ListNode dummy = new ListNode(-1);
ListNode pre = dummy;
for (int num : nums) {
pre.next = new ListNode(num);
pre = pre.next;
}
return dummy.next;
}
public static void printListNode(ListNode node) {
String s = "";
ListNode p = node;
while (p != null) {
s += p.val + "->";
p = p.next;
}
System.out.println(s+"null");
}
}