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#include <bits/stdc++.h>

using namespace std;

typedef long long int LL;

#define st first
#define nd second
#define PLL pair <LL, LL>
#define PII pair <int, int>

const int N = 3e5 + 7;
const int T = 1 << 19;
const int MX = 1e9 + 7;

int n;
LL a[N], r[N];

set <PLL> S;
vector <PII> Ranges;

int Left[N];
int Right[N];

LL tree[T + T];
int rtree[2][T + T];

void read() {
	scanf("%d", &n);
	for(int i = 1; i <= n; ++i) {
		scanf("%lld %lld", &a[i], &r[i]);
		S.insert({a[i], i});
	}
}

int getLeft(LL v) {
	auto it = S.lower_bound({v, 0});
	return (*it).nd;
}

int getRight(LL v) {
	auto it = S.lower_bound({v + 1, 0});
	return (*--it).nd;
}

void add(int p, LL v) {
	p += T;
	while(p) {
		tree[p] += v;
		p >>= 1;
	}
}

LL query(int from, int to) {
	LL ret = 0;
	from += T, to += T;
	
	while(from <= to) {
		if(from & 1)
			ret += tree[from];
		
		if(!(to & 1))
			ret += tree[to];
		
		from = (from + 1) >> 1;
		to = (to - 1) >> 1;
	}
	
	return ret;
}

void push(int t, int p, int v, function <int (int, int)> fun) {
	p += T;
	rtree[t][p] = v;
	
	while(p) {
		p >>= 1;
		rtree[t][p] = fun(rtree[t][p + p], rtree[t][p + p + 1]);
	}
}

int ask(int t, int from, int to, function <int (int, int)> fun) {
	int ret = t ? 0 : n + 1;
	from += T, to += T;

	while(from <= to) {
		if(from & 1)
			ret = fun(ret, rtree[t][from]);
		
		if(!(to & 1))
			ret = fun(ret, rtree[t][to]);
		
		from = (from + 1) >> 1;
		to = (to - 1) >> 1;
	}
	
	return ret;
}

void propagateRanges() {
	vector <int> idx(n);
	iota(idx.begin(), idx.end(), 1);
	sort(idx.begin(), idx.end(), [&](const int &fa, const int &fb) {
		return r[fa] > r[fb];
	});
	
	for(int t = 0; t < 2; ++t)
		for(int i = 0; i < T + T; ++i)
			rtree[t][i] = t ? 0 : n + 1;
	
	auto min_fun = [](const int fa, const int fb) -> int {
		return min(fa, fb);
	};

	auto max_fun = [](const int fa, const int fb) -> int {
		return max(fa, fb);
	};
	
	for(const auto &i: idx) {
		Left[i] = min(Left[i], ask(0, Left[i], Right[i], min_fun));
		Right[i] = max(Right[i], ask(1, Left[i], Right[i], max_fun));
		
		push(0, i, Left[i], min_fun);
		push(1, i, Right[i], max_fun);
	}
}

void getRanges() {
	vector <PII> cur = {{0, 0}};
	for(int i = 1; i <= n; ++i) {
		int left = getLeft(a[i] - r[i]);
		while(cur.back().nd >= left) {
			left = min(left, cur.back().st);
			cur.pop_back();
		}
		
		Left[i] = left;
		cur.push_back({left, i});
	}
	
	cur = {{n + 1, n + 1}};
	for(int i = n; i >= 1; --i) {
		int right = getRight(a[i] + r[i]);
		while(cur.back().st <= right) {
			right = max(right, cur.back().nd);
			cur.pop_back();
		}
		
		Right[i] = right;
		cur.push_back({i, right});
	}
	
	propagateRanges();
//	for(int i = 1; i <= n; ++i)
//		printf("Left[%d] = %d, Right[%d] = %d\n", i, Left[i], i, Right[i]);
}

void solve() {
	getRanges();
	for(int i = 1; i <= n; ++i)
		Ranges.push_back({Left[i], Right[i]});

	sort(Ranges.begin(), Ranges.end(), [](const PII &fa, const PII &fb) {
		if(fa.nd == fb.nd)
			return fa.st > fb.st;
		return fa.nd < fb.nd;
	});
	
	Ranges.erase(unique(Ranges.begin(), Ranges.end()), Ranges.end());
	
	int ans = 1;
	add(0, 1);
	
	for(auto [lt, rt]: Ranges) {
		int tmp = query(0, lt - 1) % MX;
//		printf("for %d %d we have %d\n", lt, rt, tmp);
		ans = (ans + tmp) % MX;
		add(lt, tmp);
	}
	
	printf("%d\n", ans);
}

int main() {
	read();
	solve();
	return 0;
}