#include <iostream>
#include <sstream>
#include <cmath>
#include <algorithm>
#include <utility>
#include <functional>
#include <iomanip>
#include <typeinfo>
#include <iterator>
#include <string>
#include <vector>
#include <queue>
#include <deque>
#include <tuple>
#include <map>
#include <set>
#include <numeric>
using namespace std;

#define sortall(container) (sort(container.begin(), container.end()))
#define yn(cond) (cond ? (cout << "Yes" << endl) : (cout << "No" << endl))
#define YN(cond) (cond ? (cout << "YES" << endl) : (cout << "NO" << endl))
#define LLONG_MAX numeric_limits<long long>::max()
#define INT_MAX numeric_limits<int>::max()

typedef long long       ll;
typedef vector<int>     vi;
typedef vector<ll>      vll;
typedef vector<double>  vd;
typedef vector<bool>    vb;
typedef vector<string>  vs;
typedef vector<char>    vc;
typedef pair<int, int>  pii;
typedef pair<ll, ll>    pll;
typedef vector<pii>     vpii;
typedef vector<pll>     vpll;
typedef vector<vll>		vvll;
typedef vector<vi>		vvi;
typedef vector<vb>		vvb;
typedef vector<vc>		vvc;

typedef struct edge_ {
	ll to;
	ll cost; 
} edge;

constexpr double	PI = 3.14159265358979323846;
constexpr ll		INF = 1 << 15;
constexpr ll		MOD = (ll)1e9 + 7;
constexpr double	EPS = 1e-7;
constexpr int		dy4[4] = { 0, 1, 0, -1 };
constexpr int		dx4[4] = { 1, 0, -1, 0 };
constexpr int		dy8[8] = { 0, 1, 1, 1, 0, -1, -1, -1 };
constexpr int		dx8[8] = { 1, 1, 0, -1, -1, -1, 0, 1 };

template <int mod>
class modint {
private:
	long long num;
	modint set(int _num) { num = _num % mod; return *this; }

public:
	modint() { num = 0; }
	modint(int num) : num(num % mod) {}

	modint operator =  (const int& x) { return set(x % mod); }
	modint operator +  (const int& x) { return modint<mod>(num + (x % mod)); }
	modint operator -  (const int& x) { return modint<mod>(num - (x % mod)); }
	modint operator *  (const int& x) { return modint<mod>(num * (x % mod)); }
	modint operator /  (const int& x) { return modint<mod>(num / (x % mod)); }
	modint operator += (const int& x) { return set(num + (x % mod)); }
	modint operator -= (const int& x) { return set(num - (x % mod)); }
	modint operator *= (const int& x) { return set(num * (x % mod)); }

	friend ostream& operator << (ostream& os, const modint<mod>& x) {
		os << x.num;
		return os;
	}
};

template<typename T>
istream& operator >> (istream& is, vector<T>& vec) {
	for (T& x : vec) is >> x;
	return is;
}

template<typename T>
ostream& operator << (ostream& os, const vector<T>& vec) {
	for (const T& x : vec) os << x << " ";
	return os;
}

template<typename S, typename T>
istream& operator >> (istream& is, pair<S, T>& p) {
	is >> p.first >> p.second;
	return is;
}

template<typename S, typename T>
ostream& operator << (ostream& os, const pair<S, T>& p) {
	os << "{" << p.first << " " << p.second << "}";
	return os;
}

/******************************************************************************/
/**********************         Don't make WA !!         **********************/
/******************************************************************************/

int main()
{
	int N;
	cin >> N;
	vpii red(N), blue(N);
	cin >> red >> blue;

	sortall(red);
	sortall(blue);

	int ans = 0;
	for (int i = 0; i < N; i++) {
		auto b = blue[i];
		int ridx = -1;
		for (int j = 0; j < red.size(); j++) {
			auto r = red[j];
			if (r.first < b.first && r.second < b.second && ridx == -1) {
				ridx = j;
				continue;
			}
			if (r.first < b.first && r.second < b.second && red[ridx].second < r.second)
				ridx = j;
		}
		if (ridx < 0) continue;
		red.erase(red.begin() + ridx);
		ans++;
	}

	cout << ans << endl;

	return 0;
}

Measured memory_bytes: 256