#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 200010;
int n, l[N], r[N], tr[N], f[N], ans;
vector<int> upd[N];
int lowbit(int i) { return i & -i; }
void update(int x, int k) {
for (int i = x; i <= n; i += lowbit(i)) tr[i] = max(tr[i], k);
}
int query(int x) {
int res = 0;
for (int i = x; i > 0; i -= lowbit(i)) res = max(res, tr[i]);
return res;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cin >> n;
for (int i = 1; i <= n; i++) cin >> l[i] >> r[i];
for (int i = 1; i <= n; i++) {
if (i - 1 <= l[i]) f[i] = 1;
else f[i] = query(i - l[i] - 1) + 1;
ans = max(ans, f[i]);
upd[min(n, i + r[i])].push_back(i);
for (int j : upd[i]) update(j, f[j]);
}
cout << ans << "\n";
return 0;
}
