import java.util.ArrayList;
import java.util.Comparator;
import java.util.Scanner;

public class Main {
public static long N = 100010;
private static int[] a;
private static ArrayList[HTML_REMOVED] list = new ArrayList();

public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    int n = scanner.nextInt();
    for (int i = 0; i < n; i++){
        a = new int[2];
        a[0] = scanner.nextInt();
        a[1] = scanner.nextInt();
        list.add(a);
    }
    list.sort(new Comparator<int[]>(){
        @Override
        public int compare(int[] o1,int[] o2){
            return o1[0] - o2[0];
        }
    });
    int k = 0;
    int r = Integer.MIN_VALUE;
    for (int[] arr : list){
        if(arr[0] > r){
            k++;
        }
        r = Math.max(r,arr[1]);
    }
    System.out.println(k);
}

}