#include <bits/stdc++.h>
using namespace std;
#define int long long
const int INF = numeric_limits<int>::max();
struct Node {
int min_val, max_val, max_dp;
};
void update(int v, int tl, int tr, int i, vector<Node>& tree, const vector<pair<int, int>>& segments, const vector<int>& dp) {
if (tl == tr) {
tree[v] = {tl, tl, dp[tl]};
} else {
int tm = (tl + tr) / 2;
if (i <= tm)
update(2 * v, tl, tm, i, tree, segments, dp);
else
update(2 * v + 1, tm + 1, tr, i, tree, segments, dp);
tree[v] = {
min(tree[2 * v].min_val, tree[2 * v + 1].min_val),
max(tree[2 * v].max_val, tree[2 * v + 1].max_val),
max(tree[2 * v].max_dp, tree[2 * v + 1].max_dp)
};
}
}
int query(int v, int tl, int tr, int x, const vector<Node>& tree) {
if (x <= tree[v].min_val) return 0;
if (x > tree[v].max_val) return tree[v].max_dp;
int tm = (tl + tr) / 2;
int a = query(2 * v, tl, tm, x, tree);
int b = query(2 * v + 1, tm + 1, tr, x, tree);
return max(a, b);
}
void solve() {
int n;
cin >> n;
vector<Node> tree(4 * n, {INF, INF, -1});
vector<int> dp(n, 1);
vector<pair<int, int>> segments(n);
for (int i = 0; i < n; ++i) {
int l, r;
cin >> l >> r;
segments[i] = {l, r};
}
vector<vector<int>> upd(n);
for (int i = 0; i < n; ++i) {
int l = segments[i].first;
int r = segments[i].second;
int mx_j = query(1, 0, n - 1, i - l, tree);
dp[i] = max(dp[i], mx_j + 1);
upd[min(n - 1, i + r)].push_back(i);
for (int j : upd[i]) {
update(1, 0, n - 1, j, tree, segments, dp);
}
}
cout << *max_element(dp.begin(), dp.end()) << endl;
}
signed main() {
solve();
return 0;
}
