#include <bits/stdc++.h>
using namespace std;
#define int long long
const int INF = 1e18;
const int MOD = 1e9+7;
const int MAXN = 2e5;
int n, m;
int arr[MAXN+5][5];
int dp[MAXN+5];
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;
void mulaidarinol(){}
void solve(){
cin >> n;
for(int i = 1; i <= n; i++) cin >> arr[i][0] >> arr[i][1];
vector<pair<int, int>> v;
for(int i = 1; i <= n; i++) v.push_back({i - arr[i][0], i});
sort(v.begin(), v.end());
int mx = 0;
for(auto [kiri, idx] : v){
while(!pq.empty() && pq.top().first < idx && pq.top().second < kiri){
mx = max(dp[pq.top().second], mx);
pq.pop();
}
dp[idx] = mx + 1;
pq.push({idx + arr[idx][1], idx});
}
int ans = 0;
for(int i = 1; i <= n; i++){
ans = max(dp[i], ans);
// cerr << "\n" << i << " : " << dp[i] << endl;
}
cout << ans << endl;
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int tc = 1;
// cin >> tc;
while(tc--){
// mulaidarinol();
solve();
}
return 0;
}
