#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()
struct segtree{
vector<int>d;
void init(int n){
d.resize(4*n+4);
build(1,0,n);
}
void build(int v,int l,int r){
if(l==r){
d[v]=0;
return;
}
int mid=(l+r)>>1;
build(v*2,l,mid);
build(v*2+1,mid+1,r);
d[v]=0;
}
int query(int v,int l,int r,int L,int R){
if(L>R||l>R||L>r) return 0;
if(L<=l&&r<=R){
return d[v];
}
int mid=(l+r)>>1;
return max(query(v*2,l,mid,L,R),query(v*2+1,mid+1,r,L,R));
}
void update(int v,int l,int r,int pos,int val){
if(r<pos||pos<l) return;
if(l==r){
d[v]=val;
return;
}
int mid=(l+r)>>1;
update(v*2,l,mid,pos,val);
update(v*2+1,mid+1,r,pos,val);
d[v]=max(d[v*2],d[v*2+1]);
}
};
int main(){
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
int n;
cin>>n;
int l[n+5],r[n+5];
vector<int>v[n+5];
for(int i=1;i<=n;i++){
cin>>l[i]>>r[i];
int R=min(i+r[i]+1,n+1);
v[R].pb(i);
}
vector<int>dp(n+5,0);
segtree sg;
sg.init(n);
for(int i=1;i<=n;i++){
for(int j:v[i]){
sg.update(1,0,n,j,dp[j]);
}
int L=max(i-l[i]-1,0);
dp[i]=sg.query(1,0,n,0,L)+1;
}
int ans=0;
for(int i=1;i<=n;i++){
ans=max(ans,dp[i]);
}
cout<<ans;
}
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