#include <bits/stdc++.h>
using namespace std;
struct act{
	int st,ed;
}a[1005];
int cnt,t;
bool cmp(act b,act c){
	return b.ed < c.ed;
}
int main(int argc, char **argv){
	int n;
	cin >> n;
	for (int i = 0;i < n;i++){
		cin >> a[i].st >> a[i].ed;
	}
	sort(a,a + n,cmp);
	for(int i = 0;i < n;i++){
		if (a[i].st >= t){
			t = a[i].ed;
			cnt++;
		}
	}
	cout << cnt;
	return 0;
}

#include<bits/stdc++.h>

using namespace std;

struct ji{
	int s_t;
	int e_t;
};

ji ni[1145];

bool codm(ji a, ji b){
	return a.e_t < b.e_t;
	
}

int main(){
	int n;
	cin >> n;
	for(int i = 0 ;i < n; i++){
		cin >> ni[i].s_t >> ni[i].e_t; 
	}
	sort(ni, ni + n, codm);
	int cnt = 0;
	int cuagain = 0;
	for(int i = 0 ; i < n; i++){
		if(ni[i].s_t >= cuagain){
			cnt++;
			cuagain = ni[i].e_t;
		}
	}
	cout << cnt << endl;
	return 0;
} 

#include<iostream>
#include<algorithm>
using namespace std;
struct huodong{
	int begin;
	int end;
};
huodong a[int(1e6)];
bool c(huodong a,huodong b){
	return a.end<b.end;
}
int main(){
	int n;
	cin>>n;
	for(int i=0;i<n;i++)
	cin>>a[i].begin>>a[i].end;
	sort(a,a+n,c);
	int t=0;
	int sum=0;
	for(int i=0;i<=n;i++)
	if(a[i].begin>=t){
		sum++;
		t=a[i].end;
	}
	cout<<sum;
}