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

using namespace std;

typedef long long I;
#define IMIN LLONG_MIN
#define IMAX LLONG_MAX

#define POCZ  0
#define SROD  1
#define KONI  3

#define N 1000000007LL

#define D(x) 

struct P {
    I p,k;
    I s;
    I res;
    void print() {
        cout  <<  "s:" << (s>>2)  << " r:" << (s&3) << " p:" << (p>>2)  << " k:" << (k>>2)  << " res:" << res << "\n";
    }
    bool pokrywa(P &a) {
        //return p<=a.p && k>=a.k;
        return k>=a.k;
    }
};

vector<P> t;

map<I,int> scale;

I a,r;
#define MAX 1048576
I resMap[2*MAX+20];
void resMapAdd(int pos, I w) {
    if(pos < 1) return;
    resMap[pos] = (resMap[pos]+ w) % N;
    return resMapAdd(pos/2, w);
}
I resMapSum(int a, int b, int ma = 0, int mb = MAX, int pos = 1) {
    if (a <= ma && mb <= b) return resMap[pos];
    if (mb <= a || b <= ma) return 0;
    int mc = (ma+mb)/2;
    return resMapSum(a, b, ma, mc, 2*pos) + resMapSum(a, b, mc, mb, 2*pos+1);
}

struct PL {
    int p,k;
    void poszerz(PL v) {
        p = min(p, v.p);
        k = max(k, v.k);
    }
};

PL placMap[2*MAX+20];
void _placMapAdd(int pos, PL w) {
    if(pos < 1) return;
    placMap[pos].poszerz(w);
    return _placMapAdd(pos/2, w);
}
void placMapAdd(int pos, PL w) { _placMapAdd(pos+MAX, w); }

void placMapPoszerz(int a, int b, PL &v, int ma = 0, int mb = MAX, int pos = 1) {
    if (a <= ma && mb <= b) return v.poszerz(placMap[pos]);
    if (mb <= a || b <= ma) return;
    int mc = (ma+mb)/2;
    placMapPoszerz(a, b, v, ma, mc, 2*pos);
    placMapPoszerz(a, b, v, mc, mb, 2*pos+1);
}

int main()
{
    for(int i=0;i<2*MAX+20;i++) placMap[i] = PL{MAX, 0};
    scale[IMIN]=0;
    scale[IMAX]=0;

    int n;
    scanf(" %d", &n);

    while(n--) {
        scanf("%lld %lld", &a ,&r);
        I p =((a-r)<<2) + POCZ ,k = ((a+r)<<2) + KONI,s = (a<<2) + SROD;
        P v = {p ,k , s, 0};
        t.push_back(v);
        scale[p]=0;
        scale[k]=0;
        scale[s]=0;
    }

    int ss = 0;
    for(auto &v: scale) {
        v.second = ss++;
        D(cout << v.first << " - " << v.second << "\n");
    }
    for(auto &v: t) {
        v.p = scale[v.p];
        v.k = scale[v.k];
        v.s = scale[v.s];
    }

    sort(t.begin(), t.end(), [](P& a, P& b) { if(a.s == b.s) return a.k > b.k; else return a.s < b.s;});

    D(cerr << "wyzn placki, nie wiem co tu wlasciwie robie\n");

    for(int i=0;i<t.size();i++) {
        placMapAdd(t[i].s, PL{t[i].p, t[i].k});
    }

    for(int wtf=0;wtf<2;wtf++) { //WTF?
    for(int i=0;i<t.size();i++) {
        PL v = PL{t[i].p, t[i].k};
        placMapPoszerz(t[i].p, t[i].k, v);
        t[i].p = v.p; t[i].k = v.k;
        placMapAdd(t[i].s, v);
    }
    for(int i=t.size()-1;i>=0;i--) {
        PL v = PL{t[i].p, t[i].k};
        placMapPoszerz(t[i].p, t[i].k, v);
        t[i].p = v.p; t[i].k = v.k;
        placMapAdd(t[i].s, v);
    }
    }


    for(auto p: t) {
        D(p.print());
    }

    D(cerr << "placki gotowe\n");

    D(cout << "!!!! Placki !!!\n");
    for(auto p: t) {
        D(p.print());
    }

    sort(t.begin(), t.end(), [](P& a, P& b) { if(a.p == b.p) return a.k > b.k; else return a.p < b.p;});
    auto last = unique(t.begin(), t.end(), [](P& a, P& b) { return a.k == b.k && a.p == b.p;});
    t.erase(last, t.end());

    D(cout << "!!!! sorted unique Placki !!!\n");
    for(auto p: t) {
        D(p.print());
    }

    resMapAdd(0+MAX,1);
    for(int i=0;i<t.size();i++) {
        I w = resMapSum(0, t[i].k);
        D(cout << "i: " << i << " res:" << w << "\n");
        resMapAdd(t[i].k+MAX, w);
    }

    D(cout << "!!!! Wynik !!!\n");
    for(auto p: t) {
        D(p.print());
    }
    cout << resMap[1] << "\n";
}