#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <vector>
#include <algorithm>
#define MAXN 200000
using namespace std;
vector<int> L(MAXN);
vector<int> R(MAXN);
vector<vector<int>> U(MAXN);
vector<int> dp(MAXN + 1);
vector<int> T(4 * MAXN);
int N;
void Update(int lo, int hi, int v, int i) {
if (lo == hi) {
T[v] = dp[i];
return;
}
int mid = (lo + hi) / 2;
if (i <= mid)
Update(lo, mid, 2 * v + 1, i);
else
Update(mid + 1, hi, 2 * v + 2, i);
T[v] = max(T[2 * v + 1], T[2 * v + 2]);
}
int Query(int lo, int hi, int v, int qlo, int qhi) {
if (qlo <= lo && hi <= qhi)
return T[v];
if (qlo > hi || qhi < lo)
return 0;
int mid = (lo + hi) / 2;
int maxLeft = Query(lo, mid, 2 * v + 1, qlo, qhi);
int maxRight = Query(mid + 1, hi, 2 * v + 2, qlo, qhi);
return max(maxLeft, maxRight);
}
int main() {
scanf("%d", &N);
for (int i = 0; i < N; ++i) {
scanf("%d %d", &L[i], &R[i]);
if (i - L[i] - 1 >= 0)
U[i - L[i] - 1].push_back(i);
}
for (int i = N - 1; i >= 0; --i) {
for (int j : U[i])
Update(0, N - 1, 0, j);
dp[i] = i + R[i] + 1 <= N - 1 ? Query(0, N - 1, 0, i + R[i] + 1, N - 1) + 1 : 1;
if (!L[i])
Update(0, N - 1, 0, i);
}
printf("%d\n", *max_element(dp.begin(), dp.begin() + N));
}
