#include<bits/stdc++.h>
// #include <ext/pb_ds/tree_policy.hpp>
// #include <ext/pb_ds/assoc_container.hpp>
using namespace std;
#define int long long
const int N = 2e5+5;
const int mod = 1e9 + 7;
const int mod1 = 998244353;
const int LG = 20;
// #define s(i) (*s.find_by_order(i)) // Warning : Read this line.
int power(int b,int e){
if(e<=0)return 1;
int o = power(b,e>>1);
o *= o, o %= mod1;
if(e % 2)o *= b, o %= mod1;
return o;
}
int val[N<<2];int n;
void update(int i,int x,int cur = 1,int st = 1,int en = n){
val[cur] = max(val[cur] , x);
if(st == en)return;
int mid = (st + en) / 2;
if(i <= mid)update(i,x,cur*2,st,mid);
else update(i,x,cur*2+1,mid+1,en);
}
int get(int l,int r,int cur = 1,int st = 1,int en = n){
if(l > r)return 0;
if(l <= st and en <= r)return val[cur];
if(en < l or r < st)return 0;
int mid = (st + en) / 2;
return max(get(l,r,cur*2,st,mid),get(l,r,cur*2+1,mid+1,en));
}
void solve(){
cin >> n;
vector<pair<int,int>> v(n + 1);
for(int i = 1 ; i <= n ;i ++){
cin >> v[i].first >> v[i].second;
v[i].first = min(v[i].first, i - 1);
v[i].second = min(v[i].second, n - i );
}
vector<vector<int>> ids(n + 1);vector<int> dp(n + 1);
for(int i = 1 ; i <= n ; i ++){
dp[i] = 1 + get(1,i-v[i].first-1);
ids[i+v[i].second].push_back(i);
for(int Id : ids[i])
update(Id, dp[Id]);
}
int ans = 0;
for(int i = 0 ; i <= n ; i ++)ans=max(ans,dp[i]);
cout << ans << '\n';
}
signed main(){
ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
int t = 1;
// cin >> t;
while(t --){
solve();
}
}
