// c
#include <bits/stdc++.h>
#include <string>
using namespace std;

#define rep(i,n) for(int i=0;i<(n);i++)

typedef long long ll;

#define REP(i,n) for(ll i=0;i<(ll)(n);i++)
#define REPD(i,n) for(ll i=n-1;i>=0;i--)
#define FOR(i,a,b) for(ll i=a;i<=(ll)(b);i++)
#define FORD(i,a,b) for(ll i=a;i>=(ll)(b);i--)
//定数
#define INF 1000000000 //10^9:極めて大きい値,∞
//略記
#define PB push_back //vectorヘの挿入
#define MP make_pair //pairのコンストラクタ
#define F first //pairの一つ目の要素
#define S second　//pairの二つ目の要素


int main(){
    int n;
    cin>>n;
    vector<pair<int,int>> a(n),b(n);
    bool ac[n]={};
    rep(i,n) cin>>a[i].first>>a[i].second;
    rep(i,n) cin>>b[i].first>>b[i].second;
    sort(a.begin(),a.end());
    sort(b.begin(),b.end());
    int j=0;
    int ans=0;
    rep(i,n){
        pair<int,int> sel_b=b[i];
        int max_y=-1;
        int sel_a;
        rep(j,n){
            if(ac[j])continue;
            if(a[j].first<sel_b.first && a[j].second<sel_b.second){
                if(a[j].second>max_y){
                    max_y=a[j].second;
                    sel_a=j;
                }
            }
        }
        if(max_y>-1){
            ans++;
            ac[sel_a]=true;
        }
    }
    cout<<ans<<endl;
    return 0;
}
#include <iostream>
#include <string>
#include <cstring>
#include <algorithm>
#include <functional>
#include <cmath>
#include <set>
#include <queue>
#include <deque>
#include <vector>
#include <climits>
#include <sstream>
#include <iomanip>
#include <map>
#include <stack>
using namespace std;
typedef unsigned long long ull;
typedef long long ll;

struct EdgeMF
{
	int to;
	ll capacity;
	int reverse;
};

void addEdgeForFlow(vector<vector<EdgeMF>>& G, int from, int to, ll capacity, ll reverseCapacity)
{
	G[from].push_back({ to, capacity, (int)G[to].size() });
	G[to].push_back({ from, reverseCapacity, (int)G[from].size() - 1 });
}

ll dfsForFlow(vector<vector<EdgeMF>>& G, vector<bool>& used, int u, int t, ll f)
{
	if (u == t)
	{
		return f;
	}

	used[u] = true;
	for (auto& e : G[u])
	{
		if (used[e.to] || e.capacity <= 0)
		{
			continue;
		}

		auto d = dfsForFlow(G, used, e.to, t, min(f, e.capacity));
		if (d > 0)
		{
			e.capacity -= d;
			G[e.to][e.reverse].capacity += d;
			return d;
		}
	}

	return 0;
}

ll calcMaxFlow(vector<vector<EdgeMF>>& G, int s, int t)
{
	auto f = 0ll;
	while (true)
	{
		vector<bool> used((int)G.size());
		auto d = dfsForFlow(G, used, s, t, LLONG_MAX);
		if (d <= 0)
		{
			break;
		}
		f += d;
	}

	return f;
}


int main()
{
	int N;
	cin >> N;
	vector<int> x(2 * N);
	vector<int> y(2 * N);
	for (auto i = 0; i < 2 * N; ++i)
	{
		cin >> x[i] >> y[i];
	}

	vector<vector<EdgeMF>> G(2 * N + 2);
	for (auto i = 0; i < N; ++i)
	{
		for (auto j = N; j < 2 * N; ++j)
		{
			if (x[i] < x[j] && y[i] < y[j])
			{
				addEdgeForFlow(G, i, j, 1, 0);
			}
		}
	}
	int s = 2 * N;
	int t = s + 1;
	for (auto i = 0; i < N; ++i)
	{
		addEdgeForFlow(G, s, i, 1, 0);
		addEdgeForFlow(G, i + N, t, 1, 0);
	}

	cout << calcMaxFlow(G, s, t) << endl;

	return 0;
}