/*
██████╗ █████╗ ███████╗██╗ ██╗██╗██████╗
██╔══██╗██╔══██╗██╔════╝██║ ██║██║██╔══██╗
██████╔╝███████║███████╗███████║██║██║ ██║
██╔══██╗██╔══██║╚════██║██╔══██║██║██║ ██║
██║ ██║██║ ██║███████║██║ ██║██║██████╔╝
╚═╝ ╚═╝╚═╝ ╚═╝╚══════╝╚═╝ ╚═╝╚═╝╚═════╝
*/
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define ll long long
#define ull unsigned long long
#define ld long double
#define str string
#define ch char
#define db double
#define pb push_back
#define ff first
#define ss second
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define YES cout<<"YES\n";
#define NO cout<<"NO\n";
#define Bob cout<<"Bob\n";
#define Alice cout<<"Alice\n";
#define ordered_set tree<pair<ll, ll>, null_type,less<pair<ll,ll>>,rb_tree_tag,tree_order_statistics_node_update>
const ll MOD=1e9+7;
const ll INF = 10000000000;
bool cmp(pair<ll,ll>x, pair<ll,ll>y){
if(x.ff!=y.ff)return x.ff>y.ff;
return x.ss>y.ss;
}
void solve(){
ll n;
cin>>n;
vector<pair<ll,ll>>v(n);
for(int i=0;i<n;i++){
cin>>v[i].ff>>v[i].ss;
}
sort(all(v),cmp);
ll cnt=0,mx=-1;
for(int i=0;i<n;i++){
if(v[i].ss>mx){
cnt++;
mx=v[i].ss;
}
}
cout<<cnt;
}
signed main(){
ll t=1;
//cin>>t;
while(t--){
solve();
}
return 0;
}
