#include <bits/stdc++.h> using namespace std; #define int long long int int32_t main() { std::ios_base::sync_with_stdio(false); std::cin.tie(NULL); int n; cin>>n; vector<pair<int,int>>b(n); for(int i=0;i<n;i++) cin>>b[i].second>>b[i].first; sort(b.begin(),b.end()); vector<pair<int,int>>r; int ans=0; for(int i=n-1;i>=0;i--) { int x=b[i].second; int y=b[i].first; int f=0; //range for(auto [i,j]:r) { if(abs(x-i)<=abs(y-j)){ f=1; break; } } if(f==0) { ans++; r.push_back({x,y}); } } cout<<ans<<endl; return 0; }