#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for(int i=0; i<(int)(n); i++)

template <typename T>
class BIT {
  vector<T> bit;
public:
  BIT() {}
  // manage data in [1, n]
  BIT(int n) : bit(n + 1) {}
  
  void init() {
    fill(bit.begin(), bit.end(), 0);
  }
  
  // return sum in [1, i]
  T sum(int i){
    T s = 0;
    while(i > 0){
      s += bit[i];
      i -= i & -i;
    }
    return s;
  }
  
  // return sum in [l, r]
  T sum(int l, int r) {
    return sum(r) - sum(l-1);
  }
  
  void add(int i, T x){
    while(i < (int)bit.size()){
      bit[i] += x;
      i += i & -i;
    }
  }
};

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  int n;
  cin >> n;
  vector<pair<int, int> > p(n);
  REP (i, n)
    cin >> p[i].first >> p[i].second;

  sort(p.rbegin(), p.rend());

  BIT<int> tree(500000);
  int ret = 0;
  for (auto &pr: p) {
    int x, r;
    tie(x, r) = pr;
    tree.add(x - r + 222222, 1);
    ret = max(ret, tree.sum(x + r + 222222 - 1));
  }
  
  cout << ret << endl;

  return 0;
}