#include<bits/stdc++.h>
using namespace std;
struct Class{
	int date = 0;
	int start = 0;
	int end = 0;
};
bool cmp(Class a , Class b){
	if(a.date != b.date)return a.date < b.date;
	else{
		return a.end < b.end;
	}
}
Class classes[100005];
int main(){
	int N;
	cin >> N;
	int class_num = 0;
	memset(classes, 0 , sizeof(classes));
	for(int i = 0 ; i < N; i += 1 ){
		int d,s,t;
		cin >> d >> s >> t ;
		classes[class_num].date = d;
		classes[class_num].start = s;
		classes[class_num++].end = t;
	}
	sort(classes,classes+class_num,cmp);
	int last = 0,ans = 0;
	for(int i = 0 ; i < class_num ; i += 1 ){
		if(i != 0 && classes[i].date != classes[i-1].date){
			last = 0;
		}
		if(last <= classes[i].start){
			ans += 1;
			last = classes[i].end;
		}
	}
	cout << ans << endl;
}