#include <bits/stdc++.h>
using namespace std;
#define int long long
#define rep(i,a,b) for (int i = a; i <= b; i++)
#define per(i,a,b) for (int i = a; i >= b; i--)
#define pii pair<int,int>
#define pb push_back
#define fi first
#define se second
#define all(v) (v).begin(), (v).end()
#define endl '\n'
const int MAXN = 2e5+10;
const int INF = 1e18+10;
const int MOD = 1e9+7;
int l[MAXN], r[MAXN], seg[4*MAXN];
int query(int i, int l, int r, int li, int ri) {
if(r < l || r < li || l > ri) return 0;
if(l>=li && r <= ri) return seg[i];
int mid = (l+r)>>1;
return max(query(2*i,l,mid,li,ri), query(2*i+1,mid+1,r,li,ri));
}
void update(int i, int l, int r, int ti, int x) {
if (r < l || ti < l || ti > r) return;
if(l==r) {
seg[i] = max(seg[i],x);
return;
}
int mid = (l+r)>>1;
update(2*i, l,mid,ti,x);
update(2*i+1,mid+1,r,ti,x);
seg[i] = max(seg[2*i],seg[2*i+1]);
}
void solve() {
int n; cin >> n;
rep(i,1,n) cin >> l[i] >> r[i];
set<array<int,3>> st;
rep(i,1,n+1) {
while(!st.empty()) {
auto [id,j,v] = *st.begin();
if(id>i) break;
st.erase(st.begin());
update(1,1,n,j,v);
}
if(i>n) break;
int x = query(1,1,n,1,i-l[i]-1) + 1;
st.insert({min(n+1,i+r[i]+1),i,x});
}
cout << query(1,1,n,1,n);
}
int32_t main() {
ios_base::sync_with_stdio(0); cin.tie(nullptr);
int tt = 1;
//cin >> tt;
while (tt--) solve();
return 0;
}
