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#include <bits/stdc++.h>

using namespace std;

#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return {i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (c it = d.b; it != d.e; ++it)
    *this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(x...) " [" #x ": " << (x) << "] "

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
template <typename A, typename B>
using unordered_map2 = __gnu_pbds::gp_hash_table<A, B>;
using namespace __gnu_pbds;
template <typename T> using ordered_set =
  __gnu_pbds::tree<T, __gnu_pbds::null_type, less<T>, __gnu_pbds::rb_tree_tag,
                   __gnu_pbds::tree_order_statistics_node_update>;
// ordered_set<int> s; s.insert(1); s.insert(2);
// s.order_of_key(1);    // Out: 0.
// *s.find_by_order(1);  // Out: 2.

using ld = long double;
using ll = long long;

constexpr int mod = 1000 * 1000 * 1000 + 7;
constexpr int odw2 = (mod + 1) / 2;

void OdejmijOd(int& a, int b) { a -= b; if (a < 0) a += mod; }
int Odejmij(int a, int b) { OdejmijOd(a, b); return a; }
void DodajDo(int& a, int b) { a += b; if (a >= mod) a -= mod; }
int Dodaj(int a, int b) { DodajDo(a, b); return a; }
int Mnoz(int a, int b) { return (ll) a * b % mod; }
void MnozDo(int& a, int b) { a = Mnoz(a, b); }
int Pot(int a, ll b) { int res = 1; while (b) { if (b % 2 == 1) MnozDo(res, a); a = Mnoz(a, a); b /= 2; } return res; }
int Odw(int a) { return Pot(a, mod - 2); }
void PodzielDo(int& a, int b) { MnozDo(a, Odw(b)); }
int Podziel(int a, int b) { return Mnoz(a, Odw(b)); }
int Moduluj(ll x) { x %= mod; if (x < 0) x += mod; return x; }

template <typename T> T Maxi(T& a, T b) { return a = max(a, b); }
template <typename T> T Mini(T& a, T b) { return a = min(a, b); }

constexpr int nax = 300 * 1000 + 10;

int n;
ll A[nax];
ll R[nax];
int pierwszy_nachodzacy[nax];
int dp[nax];

void PreprocessPierwszyNachodzacy() {
  vector<pair<ll, int>> zdarzenia;
  for (int i = 1; i <= n; i++) {
    zdarzenia.emplace_back(A[i], i);
    zdarzenia.emplace_back(A[i] + R[i], n + i);
  }
  sort(zdarzenia.begin(), zdarzenia.end());
  set<int> otwarte_przedzialy = {-1};
  for (const auto& [pos, typ] : zdarzenia) {
    if (typ > n) {
      otwarte_przedzialy.erase(typ - n);
    } else {
      pierwszy_nachodzacy[typ] = *otwarte_przedzialy.rbegin();
      otwarte_przedzialy.insert(typ);
    }
  }
}

void Preprocess() {
  PreprocessPierwszyNachodzacy();
}

int Algos() {
  Preprocess();

  vector<int> stosik_pustek = {0};
  vector<int> sum_pref = {1};
  A[0] = numeric_limits<ll>::min();
  R[0] = 0;
  dp[0] = 1;
  for (int i = 1; i <= n; i++) {
    debug() << imie(i) imie(A[i]) imie(R[i]) imie(pierwszy_nachodzacy[i]);
    const int a =
        lower_bound(stosik_pustek.begin(), stosik_pustek.end(),
                    pierwszy_nachodzacy[i])
            - stosik_pustek.begin();
    int sposoby = sum_pref.back();
    if (a > 0) OdejmijOd(sposoby, sum_pref[a - 1]);

    dp[i] = sposoby;

    debug() << imie(stosik_pustek) imie(sum_pref) imie(a) imie(dp[i]);

    while (A[i] - R[i] <= A[stosik_pustek.back()]) {
      stosik_pustek.pop_back();
      sum_pref.pop_back();
      assert(!stosik_pustek.empty());
    }
    stosik_pustek.push_back(i);
    sum_pref.push_back(Dodaj(sum_pref.back(), dp[i]));
  }

  ll haczyk = numeric_limits<ll>::max();
  int wynik = 0;
  for (int i = n; i >= 0; i--) {
    if (haczyk > A[i]) {
      DodajDo(wynik, dp[i]);
    }
    Mini(haczyk, A[i] - R[i]);
  }
  return wynik;
}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> A[i] >> R[i];
    if (i > 1) assert(A[i] > A[i - 1]);
  }

  cout << Algos() << endl;
  return 0;
}