#include <bits/stdc++.h>
using namespace std;
priority_queue < pair < int , pair <int , int> > > ramas;
int maxim[200001];
inline int Query (int indice)
{
int __maxim = 0;
for ( ; indice ; indice ^= (indice & -indice))
{ __maxim = max(__maxim , maxim[indice]); }
return __maxim;
}
inline void Update (int indice , const int valoare , const int limita)
{
for ( ; indice <= limita ; indice += (indice & -indice))
{ maxim[indice] = max(maxim[indice] , valoare); }
}
int main ()
{
ios :: sync_with_stdio(false);
cin.tie(NULL); cout.tie(NULL);
int lungime;
cin >> lungime;
int rezultat = 0;
for (int indice = 1 ; indice <= lungime ; indice++)
{
int stanga , dreapta;
cin >> stanga >> dreapta;
const int candidat = Query(max(0 , indice - stanga - 1)) + 1;
ramas.push({-(indice + dreapta) , {candidat , indice}});
while (!ramas.empty() && ramas.top().first == -indice)
{
Update(ramas.top().second.second , ramas.top().second.first , lungime);
ramas.pop();
}
rezultat = max(rezultat , candidat);
}
cout << rezultat;
return 0;
}
