#include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;

const int N = 1e5 + 10, INF = 0x3f3f3f3f;

struct Range{
    int l, r;
    bool operator< (const Range &x) const{
        return r < x.r;
    }
}range[N];

int n;

int main() {
	
    scanf("%d", &n);

    for(int i = 1; i <= n; i++) scanf("%d%d", &range[i].l, &range[i].r);

    sort(range + 1, range + n + 1);

    int ans = 0, ed = -INF;

    for(int i = 1; i <= n; i++){
        if(range[i].l > ed){
            ans++;
            ed = range[i].r;
        }
    }

    printf("%d&#92;n", ans);

	return 0;
}