#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define endl '\n'
#define ld long double
#define pb push_back
#define pf push_front
#define mod 10000007
#define se second
#define fi first
#define all(ls) (ls).begin(),(ls).end()
#define int long long
using namespace std;
using namespace __gnu_pbds;
template<typename type>using ordered_set=tree<type,null_type,less<type>,rb_tree_tag,tree_order_statistics_node_update>;
template<typename type>using ordered_multiset=tree<type,null_type,less_equal<type>,rb_tree_tag,tree_order_statistics_node_update>;
int n,t=1;
const int N=2e5+10;
vector<int>lz[N];
int seg[4*N],l[N],r[N],dp[N];
void upd(int v,int st,int en,int ind,int val){
if(st==en){
seg[v]=val;
return;
}
int mid=(st+en)/2;
if(st<=ind and ind<=mid)
upd(v*2+1,st,mid,ind,val);
if((mid+1)<=ind and ind<=en)
upd(v*2+2,mid+1,en,ind,val);
seg[v]=max(seg[v*2+1],seg[v*2+2]);
}
int get(int v,int st,int en,int l,int r){
if(st>en or st>r or en<l)
return 0;
if(l<=st and en<=r)
return seg[v];
int mid=(st+en)/2;
return max(get(v*2+1,st,mid,l,r),get(v*2+2,mid+1,en,l,r));
}
void solve(){
cin>>n;
for(int i=1;i<=n;i++){
cin>>l[i]>>r[i];
l[i]=i-l[i]-1;
r[i]=i+r[i]+1;
}
for(int i=1;i<=n;i++){
for(int j:lz[i])
upd(0,0,n+1,j,dp[j]);
if(l[i]>=1)
dp[i]=get(0,0,n+1,1,l[i])+1;
else
dp[i]=1;
lz[r[i]].pb(i);
}
cout<<*max_element(dp+1,dp+n+1)<<endl;
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
// cin>>t;
for(int i=1;i<=t;i++){
// cout<<"Scenario #"<<i<<":"<<" ";
solve();
}
}
