#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#ifdef _debug
#include </home/tony/templates/debug.cpp>
#else
#define debug(...) 42
#endif
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define pb push_back
#define vi vector<int>
#define vt vector
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
const int MOD = 1e9 + 7, inf = (int)2e9;
const ll infll = (ll)1e18;
//credit usaco guide
//segment tree is 1 indexed
template<class T> struct SegTree {
T U = -1e9; T F(T a, T b) { return max(a,b); }
int N; vector<T> t; SegTree() {}
SegTree(int N) : N(N), t(4*N,U) {}
void upd(int I, T V) { upd(I,V,1,1,N); }
void upd(int I, T V, int i, int l, int r) {
if(l==r) { t[i]=max(t[i], V); return; } int m=(l+r)/2;
if(I<=m) upd(I,V,i*2,l,m);
else upd(I,V,i*2+1,m+1,r);
t[i] = F(t[i*2], t[i*2+1]); }
T qry(int L, int R) { return qry(L,R,1,1,N); }
T qry(int L, int R, int i, int l, int r) {
if(L<=l && r<=R) return t[i];
if(R<l || L>r) return U; int m=(l+r)/2;
return F(qry(L,R,i*2,l,m), qry(L,R,i*2+1,m+1,r)); }
};
void solve(){
int N; cin >> N;
vector<int> dp(N+1, 1); //dp[i] -> answer is i choose i as the last tulip
vector<int> l(N+1), r(N+1);
for(int i = 1; i <= N; i++)cin >> l[i] >> r[i];
vector<vi> query(N+1);
for(int i = 1; i <= N; i++){
if(i - l[i] - 1 >= 1){
query[i - l[i] - 1].pb(i);
}
}
SegTree<int> st(N+1);
for(int i = 1; i <= N; i++){
if(i + r[i] <= N){
st.upd(i + r[i], dp[i]);
}
for(auto u : query[i]){
dp[u] = max(dp[u], 1 + st.qry(1, u - 1));
}
}
cout << *max_element(all(dp)) << '\n';
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0);
solve();
}
