package Unfinished; import java.util.Comparator; import java.util.Scanner; import java.util.TreeSet; /* * 直接用一个TreeSet 保存这个对象，重写一下compare方法，保证从小到大的顺序 * 再依次比较计算一下，各个对象x，y值是否递增就ok了 100% */ public class SizeMatch{ private int x ; private int y ; public SizeMatch(int x, int y) { super(); this.x = x; this.y = y; } public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); TreeSet<SizeMatch> set = new TreeSet<SizeMatch>(new Comparator<SizeMatch>() { @Override public int compare(SizeMatch o1, SizeMatch o2) { if(o1.x<o2.x){ return -1; }else if(o1.x>o2.x){ return 1; }else{ if(o1.y<o2.y){ return -1; }else if(o1.y>o2.y){ return 1; }else{ return 0; } } } }); for(int i=0;i<n;i++){ int x = sc.nextInt(); int y = sc.nextInt(); set.add(new SizeMatch(x, y)); } handler(set); sc.close(); } private static void handler(TreeSet<SizeMatch> set) { int result = 1; SizeMatch fisrt = set.first(); int x= fisrt.x; int y= fisrt.y; for(Object size : set.toArray()){ SizeMatch temp = (SizeMatch) size; if(x<temp.x&&y<temp.y){ result++; x = temp.x; y = temp.y; } } System.out.println(result); } }