#include <bits/stdc++.h> using namespace std; int main() { ios::sync_with_stdio(false); cin.tie(nullptr); int N; cin >> N; vector<long long> X(N), E(N); for (int i = 0; i < N; i++) { cin >> X[i] >> E[i]; } int ans = 0; for (int j = 0; j < N; j++) { bool influenced = false; for (int i = 0; i < N; i++) { if (i == j) continue; if (E[i] >= E[j] && llabs(X[i] - X[j]) <= E[i] - E[j]) { influenced = true; break; } } if (!influenced) ans++; } cout << ans << "\n"; return 0; }