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// Artur Kraska, II UWr

#include <bits/stdc++.h>

#define forr(i, n)                  for(int i=0; i<n; i++)
#define FOREACH(iter, coll)         for(auto iter = coll.begin(); iter != coll.end(); ++iter)
#define FOREACHR(iter, coll)        for(auto iter = coll.rbegin(); iter != coll.rend(); ++iter)
#define lbound(P,R,PRED)            ({typeof(P) X=P,RRR=(R), PPP = P; while(PPP<RRR) {X = (PPP+(RRR-PPP)/2); if(PRED) RRR = X; else PPP = X+1;} PPP;})
#define testy()                     int _tests; scanf("%d", &_tests); FOR(_test, 1, _tests)
#define CLEAR(tab)                  memset(tab, 0, sizeof(tab))
#define CONTAIN(el, coll)           (coll.find(el) != coll.end())
#define FOR(i, a, b)                for(int i=a; i<=b; i++)
#define FORD(i, a, b)               for(int i=a; i>=b; i--)
#define MP                          make_pair
#define PB                          push_back
#define ff                          first
#define ss                          second
#define deb(X)                      ;

#define M 1000000007
#define INF 1000000007LL

using namespace std;

int n, S = 1;
list <int> l;
//vector <pair<int ,int>> cofka[300007]; // <poz_powrotna, wynik>
//long long d2[2100007];
long long ress[300007];
long long* res;
int ill[1000007];
vector <pair<int, int>> v;

struct mina
{
    long long poz, range;
    int l, r;
};
mina tab[300007];

struct drzewo
{
    int minn, maks;
};
drzewo d[2100007];

struct drzewo2
{
    long long suma;
    long long maxpref;
};
drzewo2 d2[2100007];

pair<int, int> get(int nr, int pocz, int kon, int p, int k)
{
    if(p == pocz && k == kon)
        return MP(d[nr].minn, d[nr].maks);
    int s = (pocz + kon)/2;
    if(k <= s)
        return get(nr*2, pocz, s, p, k);
    if(s < p)
        return get(nr*2+1, s+1, kon, p, k);
    auto p1 = get(nr*2, pocz, s, p, s);
    auto p2 = get(nr*2+1, s+1, kon, s+1, k);
    return MP(min(p1.ff, p2.ff), max(p1.ss, p2.ss));
}

void update(int nr, int minn, int maks)
{
    nr += S;
    d[nr].minn = min(d[nr].minn, minn);
    d[nr].maks = max(d[nr].maks, maks);
    nr >>= 1;
    while(nr > 0)
    {
        d[nr].minn = min(d[nr*2].minn, d[nr*2+1].minn);
        d[nr].maks = max(d[nr*2].maks, d[nr*2+1].maks);
        nr >>= 1;
    }
}

void dokladaj(int nr, long long ile)
{
    deb(cout << "doklada " << ile << " na pozycji " << nr << endl);
    nr += S;
    d2[nr].suma += ile;
    d2[nr].maxpref = max(0ll, d2[nr].suma);
    nr >>= 1;
    while(nr > 0)
    {
        d2[nr].suma = d2[nr*2].suma + d2[nr*2+1].suma;
        d2[nr].maxpref = max(d2[nr*2].maxpref, d2[nr*2].suma + d2[nr*2+1].maxpref);
        nr >>= 1;
    }
}

// <maxpref, poz>
pair<long long, int> znajdz_dod_pref(int nr)
{
    nr += S;

    if(d2[nr].suma > 0)
        return MP(d2[nr].suma, nr-S);

    long long suma = d2[nr].suma;
    while(nr > 0)
    {
        if((nr & 1) == 0) // idziemy z lewej do gory
        {
            if(suma + d2[nr+1].maxpref > 0)
            {
                nr++;
                break;
            }
            suma += d2[nr+1].suma;
        }
        nr >>= 1;
    }

    if(nr == 0) // nie ma dod prefiksu
        return MP(0, 10000007);

    while(nr < S)
    {
        if(suma + d2[nr*2].maxpref > 0)
            nr *= 2;
        else
        {
            suma += d2[nr*2].suma;
            nr = nr*2+1;
        }
    }

    return MP(suma+d2[nr].suma, nr-S);
}

int main()
{
    scanf("%d", &n);
    FOR(i, 1, n)
    {
        scanf("%lld %lld", &tab[i].poz, &tab[i].range);
        tab[i].l = tab[i].r = i;
        l.PB(i);
    }
    FORD(i, n, 1)
        l.PB(i);

    FOR(i, 1, n)
    {
        int pocz = 1, kon = n, s;
        while(pocz < kon)
        {
            s = (pocz+kon)/2;
            if(tab[s].poz < tab[i].poz-tab[i].range)
                pocz = s+1;
            else
                kon = s;
        }
        tab[i].l = pocz;

        pocz = 1;
        kon = n;
        while(pocz < kon)
        {
            s = (pocz+kon+1)/2;
            if(tab[i].poz+tab[i].range < tab[s].poz)
                kon = s-1;
            else
                pocz = s;
        }
        tab[i].r = pocz;

//        cout << i << ": " << tab[i].l << " " << tab[i].r << endl;
    }

    while(S < n+3)
        S *= 2;

    forr(i, S)
    {
        d[i+S].minn = n+1;
        d[i+S].maks = 0;
    }
    FOR(i, 1, n)
    {
        d[i+S].minn = tab[i].l;
        d[i+S].maks = tab[i].r;
    }
    FORD(i, S-1, 1)
    {
        d[i].minn = min(d[i*2].minn, d[i*2+1].minn);
        d[i].maks = max(d[i*2].maks, d[i*2+1].maks);

        //cout << "node " << i << ": " << d[i].minn << " " << d[i].maks << endl;
    }


    while(!l.empty())
    {
        int nr = l.front();
        l.pop_front();
        auto p = get(1, 0, S-1, tab[nr].l, tab[nr].r);
        //cout << "dla " << nr << " znalazl " << p.ff << " " << p.ss << endl;
        if(p.ff < tab[nr].l || p.ss > tab[nr].r)
        {
            tab[nr].l = p.ff;
            tab[nr].r = p.ss;
            update(nr, p.ff, p.ss);
            l.PB(nr);
            ill[nr] = 0;
        }
        else
        {
            if(ill[nr] == 0)
                l.PB(nr);
            ill[nr]++;
        }
    }

    FOR(i, 1, n)
    {
        deb(cout << i << ": " << tab[i].l << " " << tab[i].r << endl);
        v.PB(MP(tab[i].r, -tab[i].l));
    }
    sort(v.begin(), v.end());

    res = (long long*)ress+2;
    res[-1] = 1;
    res[0] = 1;
    //dokladaj(0, -1);
    //dokladaj(1, 1);
    int poz = 0;

    FOR(i, 1, n)
    {
        res[i] = res[i-1];
        long long r2 = 0;
        while(poz < n && v[poz].ff == i)
        {
            long long r = 0;
            int pocz = -v[poz].ss;
            poz++;
            deb(cout << "przedzial " << pocz << " " << i << endl);
            while(1)
            {
                auto p = znajdz_dod_pref(pocz);
                if(p.ss > i) // nie ma juz dodatnich prefiksow
                    break;
                deb(cout << "znalazl prefiks " << p.ff << " na pozycji " << p.ss << endl);
                r += p.ff;
                dokladaj(p.ss, -p.ff);
            }
            if(r > 0)
                dokladaj(i+1, r);

            if(d2[pocz+S].suma == 0)
            {
            }
            if(d2[pocz+S].suma < 0)
            {
                long long ile = -d2[pocz+S].suma;
                auto p = znajdz_dod_pref(pocz+1);
                if(p.ss <= i)
                {
                    deb(cout << "tera bedzie zdejmowal prefiks krotki " << ile << " na przedziale "  << pocz << " " << p.ss << endl);
                    dokladaj(pocz, ile);
                    dokladaj(p.ss, -ile);
                }
            }
            if(d2[pocz+S].suma == 0)
            {
                deb(cout << "doklada przedzial " << pocz << " " << i << " o wadze " << res[pocz-2] << endl);
                dokladaj(pocz, -res[pocz-2]);
                dokladaj(i+1, res[pocz-2]);
                r2 += res[pocz-2];
            }
            deb(cout << " r = " << r << endl);
            r2 += r;
            deb(cout << " r2 = " << r2 << endl);
        }
        res[i] = (res[i] + r2)%M;
        deb(cout << "res[" << i << "] = " << res[i] << endl);
    }

    printf("%lld\n", res[n]);


/*    wkladaj(1, 1);
    FOR(i, 1, n)
    {
        res[i] = (res[i-1] + policz(tab[i].l-1));

        cofka[tab[i].r].PB(MP(i, res[i]));

        for(auto p : cofka[i])  // <poz_powrotna, wynik>
        {
            res[i] = (res[i] + p.ss) % M;
            wkladaj(p.ff, p.ss);
        }

        cout << "res[" << i << "] = " << res[i] << endl;
    }
    */

    return 0;
}