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#include <vector>
#include <iostream>
#include <sstream>
#include <math.h>
#include <sys/time.h>
#include <cstdlib>
#include <algorithm>
#include <cassert>
#include <cstring>
#include <fstream>
#include <set>
#include <map>
#include <iomanip>
#include <queue>

#define FOR(i,a,b)  for(__typeof(b) i=(a);i<(b);++i)
#define REP(i,a)    FOR(i,0,a)
#define FOREACH(x,c)   for(__typeof(c.begin()) x=c.begin();x != c.end(); x++)
#define ALL(c)      c.begin(),c.end()
#define CLEAR(c)    memset(c,0,sizeof(c))
#define SIZE(c) (int) ((c).size())

#define PB          push_back
#define MP          make_pair
#define X           first
#define Y           second

#define ULL         unsigned long long
#define LL          long long
#define LD          long double
#define II         pair<int, int>
#define DD         pair<double, double>
#define FF          pair<float,float>

#define VC	    vector
#define VI          VC<int>
#define VVI         VC<VI>
#define VVVI        VC<VVI>
#define VD          VC<double>
#define VS          VC<string>
#define VII         VC<II>
#define VDD         VC<DD>
#define VFF         VC<FF>
#define VVD         VC<VD>
#define VVVD        VC<VVD>
#define VULL         VC<ULL>

#define VLL2         VC<pair<LL,LL>>

#define DB(a)       cerr << #a << ": " << a << endl;

using namespace std;

template<class T> void print(VC < T > v) {cerr << "[";if (SIZE(v) != 0) cerr << v[0]; FOR(i, 1, SIZE(v)) cerr << "," << v[i]; cerr << "]\n";}
template<class T> string i2s(T &x) { ostringstream o; o << x; return o.str(); }
VS split(string &s, char c = ' ') {VS all; int p = 0, np; while (np = s.find(c, p), np >= 0) {all.PB(s.substr(p, np - p)); p = np + 1;} if (p < SIZE(s)) all.PB(s.substr(p)); return all;}

#define MOD 1000000007

int main(int argc, char *argv[]){
    int n;
    cin >> n;

    VLL2 mines(n);
    REP(i,n)
        cin >> mines[i].X >> mines[i].Y;


    VII ints(n);

    REP(i,n){
        LL l = mines[i].X-mines[i].Y;
        LL r = mines[i].X+mines[i].Y;
        int a = i, b = i;
        while(1){
            if (a > 0 && mines[a-1].X >= l){
                a--;
                l = min(l,mines[a].X-mines[a].Y);
                r = max(r,mines[a].X+mines[a].Y);
            } else if (b+1 < n && mines[b+1].X <= r){
                b++;
                l = min(l,mines[b].X-mines[b].Y);
                r = max(r,mines[b].X+mines[b].Y);
            } else
                break;
        }
        ints[i] = MP(a,b);
        //cout << i << " " << a << " " << b << endl;
    }

    sort(ALL(ints));

    VULL dp(n+2);
    dp[n] = 1;
    dp[n+1] = 1;
    int p = n-1;
    for(int i=n-1; i >= 0; i--){
        dp[i] = dp[i+1];
        while (p > 0 && ints[p].X > i) p--;
        if (ints[p].X != i) continue;

        int p2 = p;

        set<int> q;
        q.insert(ints[p].Y);
        while (p > 0 && ints[p-1].X == i){
            p--;
            q.insert(ints[p].Y);
        }

        while (!q.empty()){
            int v = *(q.begin());
            q.erase(v);
            dp[i] = (dp[i] + dp[v+2]) % MOD;
            while (p2+1 < n && ints[p2+1].X <= v+1){
                p2++;
                if (ints[p2].Y > v) q.insert(ints[p2].Y);
            }
        }
        //cout << dp[i] << endl;
    }
    //REP(i,n) cout << "(" << ints[i].X << " " << ints[i].Y << ") "; 
    //cout << endl;
    //REP(i,n+2) cout << dp[i] << " "; 
    //cout << endl;
    cout << dp[0] << endl;

    return 0;
}