#include <iostream>
#include <utility>
#include <vector>
#include <algorithm>
using namespace std;
const int decalage = (1<<18);
int tab[2*decalage];
void modify(int ind, int new_val){
tab[ind] = new_val;
while (ind > 1){
ind/=2;
tab[ind] = max(tab[ind*2], tab[ind*2+1]);
}
}
int query(int l, int r){
if (l == r) return tab[l];
if (l%2 == 1){
return max(tab[l], query(l+1,r));
}
if (r%2 == 0){
return max(tab[r], query(l,r-1));
}
return query(l/2,r/2);
}
int main(){
ios::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
int N, l, r;
cin >> N;
int skipped = 0;
int ans = 0;
vector<pair<int,int> > tulips;
vector<vector<pair<int,int> > > add (N*2);
for (int i = 0; i < N; ++i){
cin >> l >> r;
tulips.push_back(make_pair(l,r));
}
int dp[N];
int maxi = 0;
for (int i = 0; i < N; ++i){
dp[i] = 0;
}
for (int i = 0; i < N; ++i){
// for (auto s: add){
// for (auto p: s){
// cout<<p.first<<' '<<p.second<<' ';
// }
// cout<<endl;
// }
if (add[i].size() > 0){
for (auto p: add[i]){
modify(p.first+decalage,dp[p.first]);
}
}
// for (int i = decalage; i < decalage+N; ++i){
// cout<<tab[i]<<' ';
// }
// cout<<endl;
// cout<<"querying "<<i<<" 0 to "<<max(i-tulips[i].first-1,0)<<endl;
// cout<<"result "<<query(decalage,max(i-tulips[i].first-1,0) + decalage)<<endl;
dp [i] = query(decalage,max(i-tulips[i].first-1,0) + decalage) + 1;
add[tulips[i].second + i +1].push_back(make_pair(i,dp [i]));
// for (int i = 0; i < N; ++i){
// cout<<dp[i]<<' ';
// }
// cout<<endl;
// cout<<endl;
}
maxi = 0;
// for (int i = 0; i < N; ++i){
// cout<<dp[i]<<' ';
// }
// cout<<endl;
for (int i = 0; i < N; ++i ){
maxi = max(maxi, dp[i]);
}
cout<<maxi<<endl;
}
