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#include <bits/stdc++.h>
using namespace std;
#define PII pair<int, int>
#define VI vector<int>
#define VPII vector<PII>
#define LL long long
#define LD long double
#define f first
#define s second
#define MP make_pair
#define PB push_back
#define endl '\n'      // UWAGA
#define ALL(c) (c).begin(), (c).end()
#define SIZ(c) (int)(c).size()
#define REP(i, n) for(int i = 0; i < (int)(n); ++i)
#define FOR(i, b, e) for(int i = (b); i <= (int)(e); ++i)
#define FORD(i, b, e) for(int i = (b); i >= (int)(e); --i)
#define random_shuffle(V) shuffle(V, rng)

#define sim template<class n
sim, class s> ostream & operator << (ostream &p, pair<n, s> x)
{return p << "<" << x.f << ", " << x.s << ">";}
sim> auto operator << (ostream &p, n y) ->
typename enable_if<!is_same<n, string>::value, decltype(y.begin(), p)>::type 
{int o = 0; p << "{"; for(auto c: y) {if(o++) p << ", "; p << c;} return p << "}";}
void dor() {cerr << endl;}
sim, class...s> void dor(n p, s...y) {cerr << p << " "; dor(y...);}
sim, class s> void mini(n &p, s y) {if(p>y) p = y;}
sim, class s> void maxi(n &p, s y) {if(p<y) p = y;}
#ifdef DEB
#define debug(...) dor(__FUNCTION__, ":", __LINE__, ": ", __VA_ARGS__)
#else
#define debug(...)
#endif 

#define I(x) #x " =", (x), " "
#define A(a, i) #a "[" #i " =", i, "] =", a[i], " "

const int BASE = 1 << 19;
const int MXN = 300 * 1000 + 5;
LL x[MXN];
LL r[MXN];
PII seg[MXN]; // przedział który sie wysadzi jeśli zdetonujemy tę minę

namespace mines_ontak
  {
  int p[BASE*2];
  int l[BASE*2];
  void insertp(int a, int val)
    {
    a += BASE;
    while(a)
      {
      maxi(p[a], val);
      a /= 2;
      }
    }
  int queryp(int a,int b)
    {
    int res = 0;
    a += BASE - 1;
    b += BASE + 1;
    while(a/2 != b/2)
      {
      if(a % 2 == 0)maxi(res, p[a+1]);
      if(b % 2 == 1)maxi(res, p[b-1]);
      a /= 2;
      b /= 2;
      }
    return res;
    }

  void insertl(int a, int val)
    {
    a += BASE;
    while(a)
      {
      mini(l[a], val);
      a /= 2;
      }
    }
  int queryl(int a,int b)
    {
    a += BASE - 1;
    b += BASE + 1;
    int res = 1e9;
    while(a / 2 != b / 2)
      {
      if(a % 2 == 0)mini(res, l[a+1]);
      if(b % 2 == 1)mini(res, l[b-1]);
      a /= 2;
      b /= 2;
      }
    return res;
    }
  void clear(int n)
    {
    REP(i, BASE*2)p[i] = 0;
    REP(i, BASE*2)l[i] = n+1;
    }

  void preprocess(int n)
    {
    clear(n);
    x[0] = -4e18;
    x[n+1] = 4e18;
    FOR(i, 1, n)
      insertl(i, lower_bound(x+1,x+i+1,x[i]-r[i])-x);
    FOR(i, 1, n)
      insertp(i, upper_bound(x+i,x+n+1,x[i]+r[i])-x-1);

    while(1)
      {
      bool ok = 0;
      FOR(i, 1, n)
        {
        int left = queryl(l[i+BASE], p[i+BASE]);
        if(left != l[i+BASE])
          {
          ok = 1;
          insertl(i, left);
          }
        int right = queryp(l[i+BASE], p[i+BASE]);
        if(right != p[i+BASE])
          {
          ok = 1;
          insertp(i, right);
          }
        }
      if(!ok)break;
      ok = 0;

      FORD(i, n, 1)
        {
        int right = queryp(l[i+BASE], p[i+BASE]);
        if(right != p[i+BASE])
          {
          ok = 1;
          insertp(i, right);
          }
        int left = queryl(l[i+BASE], p[i+BASE]);
        if(left != l[i+BASE])
          {
          ok = 1;
          insertl(i, left);
          }
        }
      if(!ok)break;
      }
    FOR(i, 1, n)seg[i] = MP(l[i+BASE], p[i+BASE]);
    }
}


const int mod = 1e9+7;
int n;

int pref[BASE*2];
void insert(int a, int val)
  {
  a += BASE;
  while(a)
    {
    pref[a] += val;
    if(pref[a] >= mod)pref[a] -= mod;
    a /= 2;
    }
  }
int query(int b)
  {
  b += BASE+1;
  LL res = 0;
  while(b)
    {
    if(b % 2)res += pref[b-1];
    b /= 2;
    }
  return (int)(res % mod);
  }

int32_t main()
  {
  ios_base::sync_with_stdio(0);
  cin >> n;
  FOR(i, 1, n)
    {
    cin >> x[i] >> r[i];
    }
  mines_ontak::preprocess(n);
  int m = n;

  sort(seg+1, seg+n+1);
  n = unique(seg+1, seg+n+1) - seg - 1;
  sort(seg+1, seg+n+1, [&](PII a, PII b){return MP(a.f, -a.s) < MP(b.f, -b.s);});

  insert(0, 1);
  FOR(i, 1, n)
    insert(seg[i].s, query(seg[i].s-1));

  cout << query(m) << endl;
  }