#include<bits/stdc++.h>

using namespace std;

const int N = 100000;

typedef pair<int, int> PII;

PII p[N];

int main(){
    int n;
    cin>>n;
    for(int i = 0; i < n; i++)  cin>>p[i].first>>p[i].second;
    sort(p, p + n);
    priority_queue <int, vector<int>, greater<int>> q;
    for(int i = 0; i < n; i++){
        int l = p[i].first, r = p[i].second;
        if(q.empty() || l < q.top()){
            q.push(r);
        }
        else if(q.top() <= l){
            q.pop(); 
            q.push( r);
        }
    }
    cout<<q.size()<<endl;
    return 0;
}