#include <bits/stdc++.h>
using namespace std;
const int MOD = (int)1e9 + 7;
const int FFTMOD = 1007681537;
const int INF = (int)1e9;
const long long LINF = (long long)1e18;
const long double PI = acos((long double)-1);
const long double EPS = 1e-9;
inline long long gcd(long long a, long long b) {
  long long r;
  while (b) {
    r = a % b;
    a = b;
    b = r;
  }
  return a;
}
inline long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
inline long long fpow(long long n, long long k, int p = MOD) {
  long long r = 1;
  for (; k; k >>= 1) {
    if (k & 1) r = r * n % p;
    n = n * n % p;
  }
  return r;
}
template <class T>
inline int chkmin(T& a, const T& val) {
  return val < a ? a = val, 1 : 0;
}
template <class T>
inline int chkmax(T& a, const T& val) {
  return a < val ? a = val, 1 : 0;
}
inline long long isqrt(long long k) {
  long long r = sqrt(k) + 1;
  while (r * r > k) r--;
  return r;
}
inline long long icbrt(long long k) {
  long long r = cbrt(k) + 1;
  while (r * r * r > k) r--;
  return r;
}
inline void addmod(int& a, int val, int p = MOD) {
  if ((a = (a + val)) >= p) a -= p;
}
inline void submod(int& a, int val, int p = MOD) {
  if ((a = (a - val)) < 0) a += p;
}
inline int mult(int a, int b, int p = MOD) { return (long long)a * b % p; }
inline int inv(int a, int p = MOD) { return fpow(a, p - 2, p); }
inline int sign(long double x) { return x < -EPS ? -1 : x > +EPS; }
inline int sign(long double x, long double y) { return sign(x - y); }
const int maxn = 4e5 + 5;
int n;
int x[maxn][2];
int y[maxn][2];
int rem[maxn];
int f[maxn];
priority_queue<int> v[maxn << 2];
int mx[maxn << 3];
int mn[maxn << 3];
void pull(int p) {
  while (int((v[p]).size()) && rem[v[p].top()]) v[p].pop();
  int t = !int((v[p]).size()) ? -1 : v[p].top();
  if (t <= max(mx[p << 1], mx[p << 1 | 1])) {
    mx[p] = max(mx[p << 1], mx[p << 1 | 1]);
  } else {
    if (f[t] || t < min(mn[p << 1], mn[p << 1 | 1])) {
      mx[p] = -1;
    } else {
      mx[p] = t;
    }
  }
  mn[p] = max(t, min(mn[p << 1], mn[p << 1 | 1]));
}
void upd(int p, int l, int r, int L, int R, int id) {
  if (R <= l || r <= L) return;
  if (l <= L && R <= r) {
    v[p].push(id);
    pull(p);
    return;
  }
  upd(p << 1, l, r, L, L + R >> 1, id);
  upd(p << 1 | 1, l, r, L + R >> 1, R, id);
  pull(p);
}
void upd(int p, int l, int r, int L, int R) {
  if (R <= l || r <= L) return;
  if (l <= L && R <= r) {
    pull(p);
    return;
  }
  upd(p << 1, l, r, L, L + R >> 1);
  upd(p << 1 | 1, l, r, L + R >> 1, R);
  pull(p);
}
void thjchph4trjnh() {
  cin >> n;
  vector<int> dcx, dcy;
  for (int i = (0); i < (n); ++i) {
    for (int j = (0); j < (2); ++j) {
      cin >> x[i][j] >> y[i][j];
      dcx.push_back(x[i][j]);
      dcy.push_back(y[i][j]);
    }
  }
  sort((dcx).begin(), (dcx).end()),
      (dcx).erase(unique((dcx).begin(), (dcx).end()), (dcx).end());
  sort((dcy).begin(), (dcy).end()),
      (dcy).erase(unique((dcy).begin(), (dcy).end()), (dcy).end());
  static vector<pair<int, int> > events[maxn];
  for (int i = (0); i < (n); ++i) {
    for (int j = (0); j < (2); ++j) {
      x[i][j] = lower_bound((dcx).begin(), (dcx).end(), x[i][j]) - dcx.begin();
      y[i][j] = lower_bound((dcy).begin(), (dcy).end(), y[i][j]) - dcy.begin();
    }
    events[x[i][0]].push_back(make_pair(i, 0));
    events[x[i][1]].push_back(make_pair(i, 1));
  }
  for (int i = (0); i < (maxn << 3); ++i) mx[i] = -1;
  for (int i = (0); i < (maxn); ++i) {
    for (pair<int, int> e : events[i]) {
      int ix = e.first;
      if (!e.second) {
        upd(1, y[ix][0], y[ix][1], 0, maxn - 1, ix + 1);
      } else {
        rem[ix + 1] = 1;
        upd(1, y[ix][0], y[ix][1], 0, maxn - 1);
      }
    }
    while (mx[1] > 0) {
      int ix = mx[1] - 1;
      f[ix + 1] = 1;
      upd(1, y[ix][0], y[ix][1], 0, maxn - 1);
    }
  }
  cout << accumulate(f, f + maxn, 1) << "\n";
}
int main(int argc, char* argv[]) {
  ios_base::sync_with_stdio(0), cin.tie(0);
  if (argc > 1) {
    assert(freopen(argv[1], "r", stdin));
  }
  if (argc > 2) {
    assert(freopen(argv[2], "wb", stdout));
  }
  thjchph4trjnh();
  cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
  return 0;
}
