#include<bits/stdc++.h> using namespace std; const int N = 32769; long long n, ans; struct Node{ int begin, end; }a[N]; bool cmp(Node a, Node b){ return a.end < b.end; } int main(){ cin >> n; for(int i = 1;i <= n;i++) cin >> a[i].begin >> a[i].end; sort(a + 1, a + n + 1, cmp); int f = 0; for(int i = 1;i <= n;i++){ if(f < a[i].begin){ ans++; f = a[i].end; } } cout << ans; return 0; }