#include <bits/stdc++.h>
using namespace std;
#define int long long
const int INF = 1e18;
const int MOD = 1e9+7;
const int MAXN = 2e5;
#define md ((lf+rg)/2)
#define lc (pos*2)
#define rc (pos*2+1)
int n, m;
int arr[MAXN+5][5];
int dp[MAXN+5];
int segtree[MAXN+5];
void mulaidarinol(){}
void update(int idx, int val, int lf, int rg, int pos){
if(lf == rg){
segtree[pos] = val;
return ;
}
if(idx <= md) update(idx, val, lf, md, lc);
else update(idx, val, md+1, rg, rc);
segtree[pos] = max(segtree[lc], segtree[rc]);
}
int query(int ql, int qr, int lf, int rg, int pos){
if(qr < lf || rg < ql) return 0;
if(ql <= lf && rg <= qr) return segtree[pos];
int ret = max(query(ql, qr, lf, md, lc), query(ql, qr, md+1, rg, rc));
return ret;
}
void solve(){
cin >> n;
for(int i = 1; i <= n; i++) cin >> arr[i][0] >> arr[i][1];
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;
for(int i = 1; i <= n; i++){
while(!pq.empty() && pq.top().first < i){
int idx = pq.top().second;
update(idx, dp[idx], 1, n, 1);
pq.pop();
}
int kiri = max(i - arr[i][0], 1ll);
int kanan = min(i + arr[i][1], n);
// cerr << i << " : " << kiri << ' ' << kanan << endl;
if(kiri - 1 == 0) dp[i] = 1;
else dp[i] = query(1, kiri - 1, 1, n, 1) + 1;
pq.push({kanan, i});
}
int ans = 0;
for(int i = 1; i <= n; i++) ans = max(dp[i], ans);
cout << ans << endl;
// for(int i = 1; i <= n; i++) cerr << dp[i] << ' ';
// cerr << 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;
}
