#include <bits/stdc++.h>
using namespace std;
int N = 4 * 1e5 + 1;
int n;
vector<int> t(N);
vector<int>l, r;
void build() {
for (int i = n; i > 0; i--) t[i] = max(t[i << 1], t[i << 1 | 1]);
}
void update(int pos, int value) {
for (t[pos += n] = value, pos >>= 1; pos > 0; pos >>= 1) t[pos] = max(t[pos << 1], t[pos << 1 | 1]);
}
int query(int l, int r) {
l += n; r += n;
int res = 0;
for (; l < r; l >>= 1, r >>= 1) {
if (l&1) res = max(res, t[l++]);
if (r&1) res = max(res, t[--r]);
}
return res;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cin >> n;
l.resize(n); r.resize(n);
for (int i = 0; i < n; i++) {
cin >> l[i] >> r[i];
t[i + n] = 0;
}
build();
vector<int> value(n);
int ans = 0;
priority_queue <pair<int,int>, vector<pair<int,int>>, greater<pair<int,int>>> q;
for (int i = 0; i < n; i++) {
q.push(make_pair(r[i] + i, i));
while (!q.empty() && i > q.top().first) {
int j = q.top().second;
update(j, value[j]);
q.pop();
}
value[i] = query(0, max(i - l[i], 0)) + 1;
ans = max(ans, value[i]);
}
cout <<ans << '\n';
return 0;
}
