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//#pragma GCC optimize("Ofast")
//#pragma GCC optimize ("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#pragma warning(disable:4786)
#pragma warning(disable:4996)
#include <random>
#include <chrono>
#include <ctime>
#include<list>
#include <numeric>
#include<bitset>
#include<iostream>
#include<cstdio>
#include<algorithm>
#include<vector>
#include<set>
#include<map>
#include<functional>
#include<string>
#include<cstring>
#include<cstdlib>
#include<queue>
#include<utility>
#include<fstream>
#include<sstream>
#include<cmath>
#include<stack>
#include<assert.h>
#include<unordered_map>
#include<unordered_set>
#include <array>
#include <complex>
using namespace std;

#define MEM(a, b) memset(a, (b), sizeof(a))
#define CLR(a) memset(a, 0, sizeof(a))
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define ABS(X) ( (X) > 0 ? (X) : ( -(X) ) )
#define S(X) ( (X) * (X) )
#define SZ(V) (int )V.size()
#define FORN(i, n) for(int i = 0; i < n; i++)
#define FORAB(i, a, b) for(int i = a; i <= b; i++)
#define ALL(V) V.begin(), V.end()
#define IN(A, B, C)  ((B) <= (A) && (A) <= (C))
#define AIN(A, B, C) assert(IN(A, B, C))

typedef long long int LL;
//typedef __int128 LLL;
typedef long long LLL;

typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;
typedef pair<double, double> PDD;
typedef vector<int> VI;
typedef vector<LL> VL;
typedef vector<PLL> VPL;
typedef vector<PII> VP;
typedef vector<double> VD;
typedef vector<vector<int>> VVI;
typedef vector<string> VS;
typedef long double ld;

#define MAXN 203
#define MAXN2 MAXN*MAXN
//#define MAXN 1006

const LL MOD = 1000000007;
//const LL MOD = 998244353;
//const LL INF = 2000000000000000001LL; //2e18 + 1

int n;

LL tree[300005];
//return cf[idx]
LL read(int idx)
{
	LL sum = 0;
	while (idx > 0)
	{
		sum += tree[idx];
		if (sum >= MOD) sum -= MOD;
		idx -= (idx & -idx);
	}

	return sum;
}

//add val to f[idx].
//MaxVal = Just max value of index
void update(int idx, LL val)
{
	while (idx <= 300000)
	{
		tree[idx] += val;
		if (tree[idx] >= MOD) tree[idx] -= MOD;
		idx += (idx & -idx);
	}
}

VI FindNextR(VPL& V) {
	VI ret(n);
	// (where am i, left border)
	priority_queue<PLL, VPL, greater<PLL>> Q;
	for (int i = n - 1; i >= 0; i--) {
		ret[i] = i;
		while (Q.size() && Q.top().second > V[i].first) {
			Q.pop();
		}
		if (Q.size()) {
			ret[i] = Q.top().first;
		}
		Q.push({ i, V[i].first - V[i].second });
	}
	return ret;
}

VI FindNextL(VPL& V) {
	VI ret(n);
	// (where am i, right border)
	priority_queue<PLL> Q;
	for (int i = 0; i < n; i++) {
		ret[i] = i;
		while (Q.size() && Q.top().second < V[i].first) {
			Q.pop();
		}
		if (Q.size()) {
			ret[i] = Q.top().first;
		}
		Q.push({ i, V[i].first + V[i].second });
	}
	return ret;
}

VI FindSpanL(VI& nxtR) {
	VI ret(n);
	for (int i = 0; i < n; i++) {
		ret[i] = i;
	}
	for (int i = 0; i < n; i++) {
		ret[nxtR[i]] = MIN(ret[nxtR[i]], ret[i]);
	}
	return ret;
}

LL dp[300005][2];
void solve(int ks) {
	scanf("%d", &n);
	// (pos, radius).
	VPL V(n);
	for (auto& p : V) {
		scanf("%lld %lld", &p.first, &p.second);
	}

	VI nxtR = FindNextR(V);
	VI nxtL = FindNextL(V);
	VI spanL = FindSpanL(nxtR);

	stack<int> active_ones;
	for (int i = 0; i < n; i++) {
		if (i == 0) {
			dp[i][0] = dp[i][1] = 1;
			update(0 + 1, 1);
			active_ones.push(0);
			continue;
		}

		// Compute dp[i][0].
		int left_point = spanL[i];
		if (left_point == 0) {
			// I cover till "0".
			dp[i][0] = 1;
		}
		else {
			// I have someone on my left.
			dp[i][0] = (dp[left_point - 1][0] + dp[left_point - 1][1]) % MOD;
		}

		// Compute dp[i][1].
		if (nxtL[i] == i) {
			dp[i][1] = (dp[i - 1][0] + dp[i - 1][1]) % MOD;
		}
		else {
			// sum up (nxtL[i], i - 1).
			dp[i][1] = read(i - 1 + 1) - read(nxtL[i] - 1 + 1);
			if (dp[i][1] < 0) dp[i][1] += MOD;
		}
		// if there is a zero at (i), we should clean upto and including spanL[i].
		while (active_ones.size() && active_ones.top() >= left_point) {
			int id = active_ones.top();
			LL val = MOD - dp[id][1];
			if (val == MOD) val = 0;
			update(id + 1, val);
			active_ones.pop();
		}
		update(i + 1, dp[i][1]);
		active_ones.push(i);
	}
	LL ans = (dp[n - 1][0] + dp[n - 1][1]) % MOD;
	printf("%lld\n", ans);
}

void gen() {
}

int main()
{
	double start_time = clock();
#ifdef LOCAL
	freopen("C:\\Home\\Contests\\F\\sample.in", "r", stdin);
	//	freopen("out.out", "w", stdout);
#endif

	gen();

	if (0) {
		int T;
		scanf("%d", &T);
		//AIN(T, 1, 5000);
		for (int ks = 1; ks <= T; ks++) {
			solve(ks);
			//if (ks % 1 == 0) fprintf(stderr, "%d done\n", ks);
		}
	}
	else {
		solve(0);
	}

	double end_time = clock();
	fprintf(stderr, "Time = %lf\n", (end_time - start_time) / CLOCKS_PER_SEC);

	return 0;
}