#include <bits/stdc++.h>
using namespace std;
#define pi pair<int, int>
#define vi vector<int>
void update(int v, int tl, int tr, int p, int k, vector<int>& tree) {
if (tl == tr) tree[v] = k;
else {
int tm = (tl+tr)/2;
if (p <= tm) update(2*v, tl, tm, p, k, tree);
else update(2*v+1, tm+1, tr, p, k, tree);
tree[v] = max(tree[2*v], tree[2*v+1]);
}
}
int query(int v, int tl, int tr, int l, int r, vector<int>& tree) {
if (l > r) return 0;
if (tl == l && tr == r) return tree[v];
int tm = (tl+tr)/2;
int a = query(2*v, tl, tm, l, min(r, tm), tree), b = query(2*v+1, tm+1, tr, max(tm+1, l), r, tree);
return max(a, b);
}
void solve() {
int n;
cin >> n;
vector<pi> seg;
for (int i = 0; i < n; i++) {
int l, r;
cin >> l >> r;
seg.push_back(make_pair(l, r));
}
vector<int> dp(n, 1), tree(4*n, 0);
vector<vi> upd(n, vi());
int mx = 1;
for (int i = 0; i < n; i++) {
int l, r;
tie(l, r) = seg[i];
dp[i] = query(1, 0, n-1, 0, i - l - 1, tree) + 1;
mx = max(mx, dp[i]);
upd[min(i + r, n-1)].push_back(i);
for (int j : upd[i]) {
update(1, 0, n-1, j, dp[j], tree);
}
}
cout << mx << endl;
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
solve();
}
