#include <algorithm>
#include <fstream>
#include <vector>
#include <string>
#include <iomanip>
#include <iostream>
#include <sstream>
#include <cmath>
#include <set>
#define fori(n) for (int i = 0; i < (int)n; i++)
using namespace std;



struct node
{
    long long x, y, id;
};


int main()
{
    int n;
    cin >> n;
    vector<node> arr;
    for (int i = 0; i < n; ++i)
    {
        int x, y;
        cin >> x >> y;
        node help, help2;
        help.x = x; help.y = y; help.id = i;
        help2.x = y; help2.y = x; help2.id = i;
        arr.push_back(help);
        if (x != y)
            arr.push_back(help2);
    }
    sort(arr.begin(), arr.end(), [](const node& a, const node& b) -> bool
    {
        if (a.x > b.x)
            return true;
        if (a.x == b.x && a.y > b.y)
            return true;
        return false;
    });
    set<long long> maxs, ans;
    maxs.insert(10000000000000);
    for (int i = 0; i < arr.size(); ++i)
    {
        int m = -*maxs.begin();
        if (arr[i].y >= m)
        {
            ans.insert(arr[i].id);
        }
        maxs.insert(-arr[i].y);
    }
    cout << ans.size();
    return 0;
}