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#include<iostream>
#include<map>
#include<vector>
#include<algorithm>

using namespace std;

const long long INFINITY = 0x7fffffffffffffff;

const int MAX_N = 300007;
const int DEPTH = 19;
const int LEAVES = 1 << DEPTH;

inline int L(int v) {return (v << 1);}
inline int R(int v) {return ((v << 1)|1);}
inline int P(int v) {return (v >> 1);}

long long a[MAX_N], r[MAX_N];
pair<long long, int> b[MAX_N];

long long leftTreeData[MAX_N];
int leftTree[2 << DEPTH];
long long rightTreeData[MAX_N];
int rightTree[2 << DEPTH];
long long e[MAX_N];
int maxETree[2 << DEPTH];
long long s[MAX_N];
int minSTree[2 << DEPTH];

inline int merge(long long treeData[], bool type, int x, int y) {
	return (((treeData[x] >= treeData[y]) == type) ? x : y);
}

int query(int tree[], bool type, long long treeData[], int ps, int pe, int vs, int ve, int v) {
	if(pe < vs || ve < ps) return MAX_N-1;
	if(ps <= vs && ve <= pe) return tree[v];
	int split = (vs+ve)>>1;
	return merge(treeData, type, query(tree, type, treeData, ps, pe, vs, split, L(v)), query(tree, type, treeData, ps, pe, split+1, ve, R(v)));
}

inline int query(int tree[], bool type, long long treeData[], int ps, int pe) {
	if(pe < ps) return MAX_N-1;
	return query(tree, type, treeData, ps, pe, 0, LEAVES-1, 1);
}

void change(int tree[], bool type, long long treeData[], int i, long long val) {
	treeData[i] = val;
	i |= LEAVES;
	while(i = P(i)) {
		tree[i] = merge(treeData, type, tree[L(i)], tree[R(i)]);
	}
}

int FAU[MAX_N];

int fauFind(int x) {
	if(FAU[x] == x) return x;
	return FAU[x] = fauFind(FAU[x]);
}

vector<int> graf[MAX_N];

bool visited[MAX_N];

pair<int, int> sp[MAX_N];
vector<int> temp[MAX_N];

long long MOD = 1000000007;
long long dp[MAX_N];

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin >> n;
	for(int i = 0; i < n; i++) {
		cin >> a[i] >> r[i];
		b[i].first = r[i];
		b[i].second = i;
		leftTreeData[i] = rightTreeData[i] = r[i];
		leftTree[i|LEAVES] = rightTree[i|LEAVES] = minSTree[i|LEAVES] = maxETree[i|LEAVES] = i;
		FAU[i] = i;
	}
	for(int i = n; i < LEAVES; i++) {
		leftTreeData[i] = rightTreeData[i] = s[i] = e[i] = 1e9;
		leftTree[i|LEAVES] = rightTree[i|LEAVES] = minSTree[i|LEAVES] = maxETree[i|LEAVES] = i;
	}
	for(int i = 0; i < n; i++) {
		int low = -1, high = n, mid;
		while(low+1 < high) {
			mid = (low+high)>>1;
			if(a[mid] <= a[i]+r[i]) low = mid;
			else high = mid;
		}
		e[i] = low;
		low = -1, high = n;
		while(low+1 < high) {
			mid = (low+high)>>1;
			if(a[i]-r[i] <= a[mid]) high = mid;
			low = mid;
		}
		s[i] = high;
	}
	for(int i = LEAVES-1; i > 0; i--) {
		leftTree[i] = merge(leftTreeData, false, leftTree[L(i)], leftTree[R(i)]);
		rightTree[i] = merge(rightTreeData, false, rightTree[L(i)], rightTree[R(i)]);
		minSTree[i] = merge(s, false, minSTree[L(i)], minSTree[R(i)]);
		maxETree[i] = merge(e, true, maxETree[L(i)], maxETree[R(i)]);
	}
	sort(b, b+n);
	for(int i = 0; i < n; i++) {
		int x = query(minSTree, false, s, b[i].second+1, e[b[i].second]);
		if(x == MAX_N-1 || s[x] > b[i].second) {
			x = query(maxETree, true, e, s[b[i].second], b[i].second-1);
		}
		if(x == MAX_N-1 || e[x] < b[i].second) {
			int check = query(leftTree, false, leftTreeData, s[b[i].second], b[i].second-1);
			while(leftTreeData[check] < b[i].first) {
				graf[b[i].second].push_back(check);
				change(leftTree, false, leftTreeData, check, INFINITY);
				check = query(leftTree, false, leftTreeData, s[b[i].second], b[i].second-1);
			}
			check = query(rightTree, false, rightTreeData, b[i].second+1, e[b[i].second]);
			while(rightTreeData[check] < b[i].first) {
				graf[b[i].second].push_back(check);
				change(rightTree, false, rightTreeData, check, INFINITY);
				check = query(rightTree, false, rightTreeData, b[i].second+1, e[b[i].second]);
			}
		}
		else {
			int snew = min(s[x], s[b[i].second]);
			int enew = max(e[x], e[b[i].second]);
			change(minSTree, false, s, x, snew);
			change(maxETree, true, e, x, enew);
			change(minSTree, false, s, b[i].second, snew);
			change(maxETree, true, e, b[i].second, enew);
			FAU[b[i].second] = x;
		}
	}
	vector<pair<int, bool>> dfs;
	dfs.reserve(n);
	for(int i = 0; i < n; i++) {
		if(FAU[i] != i) continue;
		if(visited[i]) continue;
		dfs.clear();
		dfs.push_back(make_pair(i, true));
		while(dfs.size()) {
			pair<int, bool> x = dfs.back();
			dfs.pop_back();
			if(x.second) {
				if(visited[x.first]) continue;
				dfs.push_back(make_pair(x.first, false));
				for(auto& c : graf[x.first]) {
					if(!visited[c]) {
						visited[c] = true;
						dfs.push_back(make_pair(fauFind(c), true));
					}
				}
			}
			else {
				for(auto& c : graf[x.first]) {
					s[x.first] = min(s[x.first], s[fauFind(c)]);
					e[x.first] = max(e[x.first], e[fauFind(c)]);
				}
			}
		}
	}
	map<long long, int> scale;
	for(int i = 0; i < n; i++) {
		scale[s[i]] = 1;
		scale[e[i]] = 1;
	}
	int am = 0;
	for(map<long long, int>::iterator it = scale.begin(); it != scale.end(); it++) {
		it->second = am++;
	}
	int index = 0;
	for(int i = 0; i < n; i++) {
		if(FAU[i] == i) {
			sp[index] = make_pair(scale[s[i]], scale[e[i]]);
			index++;
		}
	}
	sort(sp, sp+index);
	for(int i = index-1; i >= 0; i--) {
		for(auto xd : temp[sp[i].second]) {
			temp[sp[i].first].push_back(xd);
		}
		temp[sp[i].first].push_back(sp[i].second);
	}
	for(int i = am; i < MAX_N; i++) {
		dp[i] = 1;
	}
	long long all = 0;
	for(int i = am-1; i >= 0; i--) {
		dp[i] = 0;
		for(auto xd : temp[i]) {
			dp[i] = (dp[i]+dp[xd+2])%MOD;
		}
		all = (all + dp[i]) % MOD;
	}
	cout << (all+1) << '\n';
	return 0;
}