#include <bits/stdc++.h>
using namespace std;
#define append push_back
#define int long long
const int N=4e5+10,LG=21;
int mod=998244353;
vector<pair<int,int>>g[N];
int dp[N],val[N];
void solve(int tst){
int n;
cin>>n;
int ans=0;
set<int>s;
for(int i=0;i<n;i++) dp[i]=1;
for(int i=0;i<n;i++){
int l,r;
cin>>l>>r;
for(auto [ind,v]:g[i]){
auto it=s.lower_bound(ind);
if(it!=s.begin()){
--it;
val[ind]=max(val[ind],val[*it]);
}
s.insert(ind);
}
int x=i-l-1,y=i+1+r;
auto it=s.lower_bound(x+1);
if(it!=s.begin()) dp[i]=max(dp[i],val[*--it]+1);
// for(auto it=s.begin();it!=s.end() and (*it).first<=x;++it) dp[i]=max(dp[i],(*it).second+1);
if(y<n) g[y].append({i,dp[i]});
ans=max(ans,dp[i]);
val[i]=dp[i];
}
cout<<ans<<endl;
}
signed main(){
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
int t = 1;
// cin >> t;
for(int i=1;i<=t;i++)
solve(i);
}
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