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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 = 500'001;
constexpr int dax = 240 * 64;

int drz[1048576 * 2];

struct Drzewo {
  Drzewo(int n_) : n(n_) {
    n2 = 1;
    while (n2 < n) n2 *= 2;
    for (int i = 0; i < n2 * 2; i++) {
      drz[i] = -1;
    }
    //drz.resize(n2 * 2, -1);
  }

  int Get(int x) {
    assert(0 <= x and x < n);
    x += n2;
    int wynik = -1;
    while (x >= 1) {
      if (drz[x] != -1) wynik = drz[x];
      x /= 2;
    }
    return wynik;
  }

  void Set(int a, int b, int value) {
    assert(0 <= a and a <= b and b < n);
    Set_(1, a, b, 0, n2 - 1, value);
  }

  void Set_(int w, int a, int b, int p, int k, int value) {
    if (b < p or k < a) {
      return;
    }
    if (a <= p and k <= b) {
      drz[w] = value;
      return;
    }
    assert(w < n2);
    if (drz[w] != -1) {
      drz[w * 2] = drz[w];
      drz[w * 2 + 1] = drz[w];
      drz[w] = -1;
    }
    Set_(w * 2, a, b, p, (p + k) / 2, value);
    Set_(w * 2 + 1, a, b, (p + k + 1) / 2, k, value);
  }

  int n;
  int n2;
  //vector<int> drz;
};

int n;
int L[nax];
int R[nax];
int A[nax];
int B[nax];
int ilewidze[nax];
uint64_t bity[nax][dax / 64];

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

  cerr << sizeof(bity) << endl;

  cin >> n;
  Drzewo drzewo(2 * n);
  for (int i = 0; i < n; i++) {
    cin >> L[i] >> R[i];
    L[i]--; R[i]--;
    assert(0 <= L[i] and L[i] < R[i] and R[i] < 2 * n);
    A[i] = drzewo.Get(L[i]);
    B[i] = drzewo.Get(R[i]);
    if (A[i] == -1) A[i] = n;
    if (B[i] == -1) B[i] = n;
    drzewo.Set(L[i], R[i], i);
  }

  for (int od = 0; od < n; od += dax) {
    for (int i = min(od + dax, n) - 1; i >= od; i--) {
      bity[i][(i - od) / 64] |= (1llu << ((i - od) % 64));
      const int a = A[i];
      const int b = B[i];
      int suma = 0;
      uint64_t maska = 0;
      for (int j = 0; j < dax / 64; j++) {
        if (!bity[i][j]) continue;
        if (maska & bity[i][j]) {
          suma += std::popcount(maska);
          maska = 0;
        }
        maska |= bity[i][j];
        bity[a][j] |= bity[i][j];
        bity[b][j] |= bity[i][j];
        bity[i][j] = 0;
      }
      suma += std::popcount(maska);
      ilewidze[i] += suma;
    }
    for (int i = od - 1; i >= 0; i--) {
      const int a = A[i];
      const int b = B[i];
      int suma = 0;
      uint64_t maska = 0;
      for (int j = 0; j < dax / 64; j++) {
        if (!bity[i][j]) continue;
        if (maska & bity[i][j]) {
          suma += std::popcount(maska);
          maska = 0;
        }
        maska |= bity[i][j];
        bity[a][j] |= bity[i][j];
        bity[b][j] |= bity[i][j];
        bity[i][j] = 0;
      }
      suma += std::popcount(maska);
      ilewidze[i] += suma;
    }
  }

  int wynik = 0;
  for (int i = n - 1; i >= 0; i--) {
    DodajDo(wynik, Odw(ilewidze[i]));
  }
  cout << wynik << endl;
  return 0;
}