/*有没有小伙伴帮忙分析一下，提交完0%……*/ import java.util.*; public class Main{ public static void main(String[] args){ Scanner sc = new Scanner(System.in); while(sc.hasNextLine()){ int n = sc.nextInt(); int[][] arr = new int[n][2]; for(int i = 0;i<n;i++){ arr[i][0]=sc.nextInt(); arr[i][1]=sc.nextInt(); } Map map = new HashMap() ; for(int i = 0;i<n;i++){ int j; for( j=i+1 ; j<n; j++){ if(arr[j][0]>arr[i][0]&&arr[j][1]>arr[i][1]) break; } if(j == n) map.put(arr[i][0],arr[i][1]); } for(Object key : map.keySet()){ System.out.println(key+" "+map.get(key)); } } sc.close(); } }