```
#include<bits/stdc++.h>
using namespace std;
int n;
struct Tsuki{
int x,y;
}a[1000010];
bool cmp(Tsuki p,Tsuki q){
return p.y<q.y;
}
int main(){
cin>>n;
for(int i=1;i<=n;i++){
cin>>a[i].x>>a[i].y;
}
sort(a+1,a+n+1,cmp);
int end=a[1].y;
int ans=1;
for(int i=2;i<=n;i++){
if(a[i].x>=end){
ans++;
end=a[i].y;
}
}
cout<<ans;
return 0;
}
by Aurora09 @ 2023-08-16 09:44:10