#include <bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
#define eb emplace_back
using namespace std;
typedef long long LL;
typedef pair<int,int> pii;
typedef vector<int> vi;
template<class T> inline T re(){
T N = 0; char c = getchar(); bool neg = 0;
for (; c < '0' || c > '9'; c = getchar()) neg |= c == '-';
for (; c >= '0' && c <= '9'; c = getchar())
N = (N<<3)+(N<<1) + c - '0';
return neg ? -N : N;
}
const int MX = 2e5;
int n;
int l[MX + 5], r[MX + 5];
int dp[MX + 5];
namespace SegTree {
int st[MX * 4 + 50];
void upd(int pos, int x, int p = 1, int l = 0, int r = n) {
if (l == r) return void(st[p] = x);
int md = (l + r) >> 1;
if (pos <= md) upd(pos, x, p << 1, l, md);
else upd(pos, x, p << 1 | 1, md + 1, r);
st[p] = max(st[p << 1], st[p << 1 | 1]);
}
int get(int i, int j, int p = 1, int l = 0, int r = n) {
if (i > j || j < l || i > r) return 0;
if (i <= l && j >= r) return st[p];
int md = (l + r) >> 1;
return max(get(i, j, p << 1, l, md), get(i, j, p << 1 | 1, md + 1, r));
}
};
using namespace SegTree;
priority_queue<pii, vector<pii>, greater<pii>> pq;
int main() {
n = re<int>();
for (int i = 1; i <= n; i++) {
l[i] = re<int>(); r[i] = re<int>();
}
dp[0] = 0;
int mx = 0;
for (int i = 1; i <= n; i++) {
while (!pq.empty() && pq.top().fi < i) {
int x = pq.top().se; pq.pop();
upd(x, dp[x]);
}
dp[i] = 1;
dp[i] = max(dp[i], get(0, i - l[i] - 1) + 1);
/*
for (int j = i - l[i] - 1; j > 0; --j) {
if (j + r[j] < i) dp[i] = max(dp[i], dp[j] + 1);
}
*/
mx = max(mx, dp[i]);
pq.emplace(i + r[i], i);
}
printf("%lld\n", mx);
return 0;
}
