#include <algorithm>
#include <cmath>
#include <cstring>
#include <iostream>
#include <iomanip>
#include <limits.h>
#include <set>
#include <string>
#include <queue>
#include <stack>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#include <deque>
#include <map>
#include <chrono>
#include <random>
#include <bitset>
#include <tuple>
#define SZ(x) int(x.size())
#define FR(i,a,b) for(int i=(a);i<(b);++i)
#define FOR(i,n) FR(i,0,n)
#define FAST ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define A first
#define B second
#define mp(a,b) make_pair(a,b)
typedef long long LL;
typedef long double LD;
typedef unsigned long long ULL;
typedef unsigned __int128 U128;
typedef __int128 I128;
typedef std::pair<int,int> PII;
typedef std::pair<LL,LL> PLL;
using namespace std;
const LL MAXN=2e5+5;
LL l[MAXN], r[MAXN], dp[MAXN];
vector<PLL> tmp[MAXN];
LL st[4*MAXN];
void update(LL id, LL lf, LL rt, LL i, LL x){
if (lf==rt){
st[id]=max(st[id],x);
return;
}
LL mid=(lf+rt)/2;
if (i<=mid) update(id*2, lf, mid, i, x);
else update(id*2+1, mid+1, rt, i, x);
st[id]=max(st[id*2], st[id*2+1]);
}
LL get(LL id, LL lf, LL rt, LL l1, LL r1){
if (r1<lf || rt<l1) return 0;
if (l1<=lf && rt<=r1) return st[id];
LL mid=(lf+rt)/2;
return max(get(id*2,lf,mid,l1,r1), get(id*2+1,mid+1,rt,l1,r1));
}
signed main(){
FAST;
LL n; cin>>n;
FR(i,1,n+1) cin>>l[i]>>r[i];
FR(i,1,n+1){
for (PLL p:tmp[i]){
LL id=p.A, x=p.B;
update(1,1,n,id,x);
}
dp[i]=1;
LL lf=i-l[i]-1;
if (lf>=1) dp[i]+=get(1,1,n,1,lf);
LL rt=i+r[i]+1;
if (rt<=n) tmp[rt].push_back(mp(i,dp[i]));
}
//FR(i,1,n+1) cout<<dp[i]<<" ";
//cout<<"\n";
LL ans=0;
FR(i,1,n+1) ans=max(ans,dp[i]);
cout<<ans;
return 0;
}