#include<bits/stdc++.h>
using namespace std;
#define sp <<' '<<
#define se second
#define fi first
#define pb push_back
#define FOR(i,a) for(int i=0;i<(a);i++)
#define FORE(i,a,b) for(int i=(a);i<(b);i++)
#define DEBUG(x) cout<<#x sp x<<endl
#define mid (l+r)/2
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef vector<pii> vii;
const int MAXN=2e5+5;
int deg[MAXN];
vi tut[MAXN];
vii a;
int n;
int t[MAXN*4];
void up(int pos,int val,int nd=1,int l=1,int r=n){
if(l==r){
t[nd]=val;
return;
}
if(pos<=mid) up(pos,val,nd*2,l,mid);
else up(pos,val,nd*2+1,mid+1,r);
t[nd]=max(t[nd*2],t[nd*2+1]);
}
int qu(int ql,int qr,int nd=1,int l=1,int r=n){
if(l>r or l>qr or r<ql) return 0;
if(ql<=l and r<=qr){
return t[nd];
}
auto s1=qu(ql,qr,nd*2,l,mid);
auto s2=qu(ql,qr,nd*2+1,mid+1,r);
return max(s1,s2);
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0);cout.tie(0);
cin>>n;
a.resize(n+1);
FORE(i,1,n+1){
cin>>a[i].fi>>a[i].se;
}
int ans=1;
FORE(i,1,n+1){
for(auto el:tut[i]){
up(el,deg[el]);
}
deg[i]=1;
if(i-a[i].fi-1>0){
deg[i]=max(deg[i],qu(1,i-a[i].fi-1)+1);
}
if(i+a[i].se+1<=n) tut[i+a[i].se+1].pb(i);
ans=max(ans,deg[i]);
}
cout<<ans<<endl;
}
