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#include <iostream>
#include <vector>
#include <algorithm>
#include <set>

using namespace std;

const long long mod = 1000000007;

int IdCount = 0;

struct Nodeqwe {
	set<Nodeqwe*> To;
	long long CombinationSum = -1;
	Nodeqwe* Bucket;
	bool Visited = false;
	int Id = IdCount++;
};

struct Mine {
	int Position;
	int Range;
	vector<Mine*> To;
	vector<Mine*> From;
	Nodeqwe* Node = NULL;
	int PostOrder = -1;
	bool Visited = false;
};

int PostOrderCount = 0;

vector<Mine*> Mines;
vector<Nodeqwe*> Nodes;

class MineComp {
public:
	bool operator()(const Mine* a, const int b) const {
		return a->Position < b;
	}

	bool operator()(const int a, const Mine* b) const {
		return a < b->Position;
	}
};

bool mineCompByPost(Mine* a, Mine* b) {
	return a->PostOrder > b->PostOrder;
}

void postOrderInsert(Mine* m) {
	if (m->Visited)
		return;

	m->Visited = true;
	for (vector<Mine*>::iterator w = m->To.begin(); w != m->To.end();w++) {
		postOrderInsert(*w);
	}
	m->PostOrder = PostOrderCount++;

	return;
}

bool findGropu(Mine* m, Nodeqwe* g) {
	if (m->Node != NULL)
		return false;

	m->Node = g;

	for (vector<Mine*>::iterator w = m->From.begin(); w != m->From.end();w++) {
		findGropu(*w, g);
	}

	return true;
}

Nodeqwe* findBucket(Nodeqwe* n) {
	if (n->Bucket == n)
		return n;

	return n->Bucket = findBucket(n->Bucket);
}

void foo(Nodeqwe* n) {
	if (n->Visited)
		return;

	n->Visited = true;
	n->Bucket = n;

	for (set<Nodeqwe*>::iterator w = n->To.begin(); w != n->To.end();w++) {
		foo(*w);
		findBucket(*w)->Bucket = n;
	}

	n->CombinationSum = 1;
	for (set<Nodeqwe*>::iterator w = n->To.begin(); w != n->To.end();w++) {
		n->CombinationSum *= (*w)->CombinationSum;
		n->CombinationSum %= mod;
	}
	n->CombinationSum++;
}

int main()
{
	int n;
	cin >> n;

	Mines.resize(n);
	for (int i = 0;i < n;i++) {
		int a, b;
		cin >> a >> b;
		Mine* m = new Mine();
		m->Position = a;
		m->Range = b;
		Mines[i] = m;
	}

	vector<Mine*>::iterator beg, end, it, fbeg, fend, fit;
	it = beg = Mines.begin();
	end = Mines.end();

	MineComp cmp;

	for (;it != end;it++) {
		Mine* mc = *it;
		fit = fbeg = lower_bound(beg, end, mc->Position - mc->Range, cmp);
		fend = upper_bound(beg, end, mc->Position + mc->Range, cmp);
		for (;fit != fend;fit++) {
			if (fit == it)
				continue;
			mc->To.push_back(*fit);
			(*fit)->From.push_back(mc);
		}
	}

	for (it = beg;it != end;it++) {
		postOrderInsert(*it);
	}

	sort(Mines.begin(), Mines.end(), mineCompByPost);

	Nodeqwe* node = new Nodeqwe();
	for (it = Mines.begin();it != Mines.end();it++) {
		if (findGropu(*it, node)) {
			Nodes.push_back(node);
			node = new Nodeqwe();
		}
	}

	for (it = Mines.begin();it != Mines.end();it++) {
		for (vector<Mine*>::iterator to = (*it)->From.begin();to != (*it)->From.end();to++) {
			if ((*it)->Node == (*to)->Node)
				continue;
			(*it)->Node->To.insert((*to)->Node);
		}
	}

	for (vector<Nodeqwe*>::iterator it = Nodes.begin();it != Nodes.end();it++) {
		foo(*it);
	}

	long long acc = 1;

	for (vector<Nodeqwe*>::iterator it = Nodes.begin();it != Nodes.end();it++) {
		if ((*it)->Bucket != *it)
			continue;

		acc *= (*it)->CombinationSum;
		acc %= mod;
	}

	cout << acc;
	return 0;
}