#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define pf push_front
#define mp make_pair
#define fi first
#define se second
#define int long long
#define all(x) (x).begin(), (x).end()
typedef long double ld;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<bool> vb;
typedef vector<vector<int>> vvi;
typedef vector<vector<bool>> vvb;
typedef vector<vector<ll>> vvll;
typedef vector<string> vs;
typedef vector<vector<string>> vvs;
typedef vector<char> vc;
typedef vector<vector<char>> vvc;
typedef map<int, int> mii;
typedef unordered_map<int, int> umii;
const int mod = 1e9 + 7;
const int inf = INTMAX_MAX;
const bool tc = false;
class SegTree {
int n;
vector<long long> tree;
public:
SegTree(int N) : n(N), tree(4 * N, 0) {}
void ps(int idx, long long val) {
setPoint(1, 0, n - 1, idx, val);
}
long long rmq(int l, int r) {
if (l > r) return 0;
return rangeMax(1, 0, n - 1, l, r);
}
private:
void setPoint(int node, int nl, int nr, int idx, long long val) {
if (nl == nr) {
tree[node] = val;
return;
}
int mid = (nl + nr) / 2;
if (idx <= mid) setPoint(2 * node, nl, mid, idx, val);
else setPoint(2 * node + 1, mid + 1, nr, idx, val);
tree[node] = max(tree[2 * node], tree[2 * node + 1]);
}
long long rangeMax(int node, int nl, int nr, int l, int r) {
if (r < nl || nr < l) return LLONG_MIN;
if (l <= nl && nr <= r) return tree[node];
int mid = (nl + nr) / 2;
return max(
rangeMax(2 * node, nl, mid, l, r),
rangeMax(2 * node + 1, mid + 1, nr, l, r)
);
}
};
inline void solve() {
int n; cin >> n;
vi l(n), r(n);
for (int i = 0; i < n; i++) cin >> l[i] >> r[i];
SegTree st(n);
vi dp(n); dp[0] = 1;
set<pii> ev; ev.insert({r[0] + 1, 0});
for (int i = 1; i < n; i++) {
vector<pii> rv;
for (auto &x : ev) {
if (x.fi == i) {
st.ps(x.se, dp[x.se]);
rv.pb(x);
}
else break;
}
for (auto &x : rv) ev.erase(x);
dp[i] = 1 + st.rmq(0, i - l[i] - 1);
ev.insert({i + r[i] + 1, i});
}
cout << *max_element(all(dp)) << '\n';
}
void setIO(string s) {
freopen((s + ".in").c_str(), "r", stdin);
freopen((s + ".out").c_str(), "w", stdout);
}
signed main() {
ios::sync_with_stdio(false);
cout.tie(0);
cin.tie(0);
//setIO();
int t = 1;
if (tc) {
cin >> t;
}
while (t--) {
solve();
}
}
