#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define all(x) (x).begin(), (x).end()
#define md ((tl + tr) >> 1)
#define TL v + v, tl, md
#define TR v + v + 1, md + 1, tr
#define F first
#define S second
#define pii pair<int, int>
#define int ll
const int maxn = 5e5 + 7;
const ll inf = 1e18 + 7;
int n;
pii p[maxn];
void solve() {
cin >> n;
for (int i = 1; i <= n; i++)
cin >> p[i].F >> p[i].S;
sort(p + 1, p + n + 1);
vector<int> v;
for (int i = 1; i <= n; i++) {
while (!v.empty() && p[i].S - p[v.back()].S >= p[i].F - p[v.back()].F)
v.pop_back();
if (v.empty() || p[v.back()].S - p[i].S < p[i].F - p[v.back()].F)
v.push_back(i);
}
cout << v.size();
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int test = 1;
// cin >> test;
while (test--) {
solve();
// cout << '\n';
}
return 0;
}
