#include<bits/stdc++.h>
#define rep(i,n) for(int i=0;i<int(n);++i)
using namespace std;
int main() {
int n;
cin>>n;
using P=pair<int,int>;
vector<P> vp(n);
rep(i,n)cin>>vp[i].first>>vp[i].second;
sort(vp.begin(),vp.end());
multiset<P> ms(vp.begin(), vp.end());
P cur = *ms.begin();
ms.erase(ms.begin());
int ans = 0;
while(!ms.empty()){
auto lb = ms.lower_bound(P(cur.second, 0));
if(lb == ms.end()) {
cur =* ms.begin();ms.erase(ms.begin());
ans++;
}else{
cur = *lb;
ms.erase(lb);
}
}
cout << ans << endl;
}