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#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#ifdef LOC
#include "debuglib.h"
#else
#define deb(...)
#define DBP(...)
#endif
using namespace std;
using   ll         = long long;
using   Vi         = vector<int>;
using   Pii        = pair<int, int>;
#define pb           push_back
#define mp           make_pair
#define x            first
#define y            second
#define rep(i, b, e) for (int i = (b); i < (e); i++)
#define each(a, x)   for (auto& a : (x))
#define all(x)       (x).begin(), (x).end()
#define sz(x)        int((x).size())

constexpr int MOD = 1e9+7;

struct Fenwick {
	vector<ll> s;
	Fenwick(int n = 0) : s(n) {}
	void update(int i, ll v) {
		for (; i < sz(s); i |= i+1) {
			s[i] = (s[i]+v) % MOD;
		}
	}
	ll query(int i) {
		ll v = 0;
		for (; i > 0; i &= i-1) {
			v = (v + s[i-1]) % MOD;
		}
		return v;
	}
};

int main() {
	cin.sync_with_stdio(0); cin.tie(0);
	cout << fixed << setprecision(10);

	int n; cin >> n;
	vector<pair<ll, ll>> mines(n);
	each(e, mines) cin >> e.x >> e.y;

	vector<Pii> elems;

	each(e, mines) {
		int first = int(lower_bound(all(mines), mp(e.x-e.y, INT64_MIN)) - mines.begin());
		int last = int(lower_bound(all(mines), mp(e.x+e.y, INT64_MAX)) - mines.begin()) - 1;
		elems.pb({first, last});
	}

	rep(cnt, 0, 2) {
		Vi left;
		rep(i, 0, sz(elems)) {
			Pii& e = elems[i];
			while (!left.empty() && left.back() >= e.x) {
				Pii& f = elems[left.back()];
				left.pop_back();
				if (e.x > f.x || e.y < f.y) cnt = 0;
				e.x = min(e.x, f.x);
				e.y = max(e.y, f.y);
			}
			left.pb(i);
		}
		each(e, elems) tie(e.x, e.y) = mp(n-e.y-1, n-e.x-1);
		reverse(all(elems));
	}

	Fenwick dp(n);
	sort(all(elems), [](Pii l, Pii r) { return mp(l.y, -l.x) < mp(r.y, -r.x); });
	elems.erase(unique(all(elems)), elems.end());
	each(e, elems) dp.update(e.x, dp.query(e.x)+1);

	ll ans = dp.query(n) + 1;
	ans %= MOD;
	if (ans < 0) ans += MOD;
	cout << ans << '\n';
	return 0;
}