#include<bits/stdc++.h>
using namespace std;
const int INF=1e9;
struct SegTreeMax {
int n; vector<int> s;
SegTreeMax(int n) : s(2*n), n(n) {}
void update(int pos, int val) {
for(s[pos+=n]=val; pos/=2;) {
s[pos]=max(s[pos*2], s[pos*2+1]);
}
}
int query(int b, int e) {
int ra=-INF, rb=-INF;
for(b+=n, e+=n; b<e; b/=2, e/=2) {
if(b%2) ra=max(ra, s[b++]);
if(e%2) rb=max(rb, s[--e]);
}
return max(ra, rb);
}
};
signed main() {
int n; cin >> n;
vector<int> l(n), r(n);
for(int i=0; i<n; i++) cin >> l[i] >> r[i];
SegTreeMax segmax(n);
priority_queue<pair<int, int>> q;
vector<int> dp(n, 1);
int ans=0;
for(int i=0; i<n; i++) {
while(!q.empty() && q.top().first == -i) {
segmax.update(q.top().second, dp[q.top().second]);
q.pop();
}
int cur=1;
if(i-l[i] > 0) cur=segmax.query(0, i-l[i])+1;
dp[i]=cur;
q.push({-(i+r[i]+1), i});
ans=max(ans, dp[i]);
}
cout << ans;
return 0;
}
