#include <bits/stdc++.h> using namespace std; #define int long long #define pi pair<int, int> #define vi vector<int> #define vs vector<string> #define vb vector<bool> #define vpi vector<pi> #define pb push_back #define all(a) (a).begin(), (a).end() const int mod = 1e9 + 7; void solve() { int n; cin >> n; vpi v(n); vi ch(n, 0); set<int> s; bool as = true; for (int i = 0; i < n; i++) { cin >> v[i].second >> v[i].first; if (i > 0 && v[i].first != v[i - 1].first) as = false; s.insert(v[i].second); } if (as) { cout << s.size() << '\n'; return; } sort(all(v)); int ans = 0, r = n - 1; while (r >= 0) { if (!ch[r]) { ans++; } ch[r] = 1; for (int r2 = r - 1; r2 >= 0; r2--) { if (v[r].first - v[r2].first >= abs(v[r].second - v[r2].second)) { ch[r2] = 1; } } r--; } cout << ans << '\n'; } signed main() { ios_base::sync_with_stdio(0); cin.tie(NULL); cout.tie(NULL); int t = 1; // cin >> t; while (t--) { solve(); } return 0; }