#include "bits/stdc++.h"
using namespace std;

#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

using ll = long long;
using pii = pair<int, int>;

const int N = 1e6 + 11;

int a[N][2];
void solve(int TC) {
	int n; cin >> n;
	for(int i = 0; i < n; i++){
		cin >> a[i][0] >> a[i][1];
	}

	int ans = 0, upper = 0;
	for(int i = n - 1; i >= 0; i--){
		if(upper > a[i][1]){
			upper = a[i][1];
		}else if(upper < a[i][0]){
			upper = a[i][1];
			ans++;
		}
	}
	cout << ans << '\n';
}

int32_t main() {
	cin.tie(0)->sync_with_stdio(0);
	cout << fixed << setprecision(10);

	int t = 1;
	// cin >> t;

	for (int i = 1; i <= t; i++) {
		solve(i);
	}
}