/************************************************
*                                               *
*     Controllare l'accampamento      VR370108  *
*                                               *
************************************************/

#include <cstdio>
#include <cassert>
#include <vector>
#include <iostream>

using namespace std;

vector <int> intervalsStart;
vector <int> intervalsEnd;
int N;

int longestIntersection(int indexStart);


int main(){
    FILE *in;
    in = fopen("input.txt", "r");
    assert(in);

    int a, b;
    fscanf(in, "%d", &N);
    
    
    for(int i = 0; i < N; i++){
        fscanf(in, "%d %d", &a, &b);
        intervalsStart.push_back(a);
        intervalsEnd.push_back(b);
    }
    
    fclose(in);

    /*for(int i = 0; i < intervalsStart.size(); i++){
            cout << intervalsStart.at(i);
            cout << " ";
            cout << intervalsEnd.at(i);
            cout << endl;
    }*/
    
    int res = longestIntersection(0);
    FILE* output;
    output = fopen("output.txt", "w");
    fprintf(output, "%d\n", res);
    
    return 0;

}

 int longestIntersection(int indexStart){  
        int fine = intervalsEnd.at(indexStart);
        int maxlungh = 0;

        bool stop = false;
        for(int i = indexStart+1; (i < intervalsStart.size() && (!stop)); i++){
            if(intervalsStart.at(i) <= fine){
                int lungh = intervalsEnd.at(i) - intervalsStart.at(i);       
                if(lungh > maxlungh){
                    maxlungh = lungh;
                    indexStart = i;
                }
            } else {
                stop = true;
                indexStart = i;
            }   
        }
        indexStart++;
        int intervalli = 0;

        if(indexStart <= N-1){
            intervalli = 1 + longestIntersection(indexStart);
        } else { 
            return intervalli;
        }

        return intervalli;
     }