// Slower C++ solution:
 #include <bits/stdc++.h>

                                        #include<iostream>

                                        #include<cstdio>

                                        #include<vector>

                                        #include<queue>

                                        #include<map>

                                        #include<cstring>

                                        #include<string>

                                        #include <math.h>

                                        #include<algorithm>

                                    //    #include <boost/multiprecision/cpp_int.hpp>

                                        #include<functional>

                               #define int long long

                                        #define inf  1000000007

                                        #define pa pair<int,int>

                                        #define ll long long

                                        #define pal pair<double,double>

                                        #define ppap pair<pa,int>

                                  

                                        #define ssa pair<string,int>

                                        #define  mp make_pair

                                        #define  pb push_back

                                        #define EPS (1e-10)

                                        #define equals(a,b) (fabs((a)-(b))<EPS)

int dx[4]={0,-1,0,1};

int dy[4]={1,0,-1,0};

                                        using namespace std;

                               			class pa3{

                                        	public:

                                        	int x,y,z;

                                        	pa3(int x=0,int y=0,int z=0):x(x),y(y),z(z) {}

                                        	bool operator < (const pa3 &p) const{

                                        		if(x!=p.x) return x<p.x;

                                        		if(y!=p.y) return y<p.y;

                                        		 return z<p.z;

                                        		//return x != p.x ? x<p.x: y<p.y;

                                        	}

                               				bool operator > (const pa3 &p) const{

                                        		if(x!=p.x) return x>p.x;

                                        		if(y!=p.y) return y>p.y;

                                        		 return z>p.z;

                                        		//return x != p.x ? x<p.x: y<p.y;

                                        	}

                                        	bool operator == (const pa3 &p) const{

                                        		return x==p.x && y==p.y && z==p.z;

                                        	}

                                        		bool operator != (const pa3 &p) const{

                                        			return !( x==p.x && y==p.y && z==p.z);

                                        	}

                                        

                                        };

                                        

                                        class pa4{

                                        	public:

                                        	double x;

                                        	int y,z,w;

                                        	pa4(double x=0,int y=0,int z=0,int w=0):x(x),y(y),z(z),w(w) {}

                                        	bool operator < (const pa4 &p) const{

                                        		if(x!=p.x) return x<p.x;

                                        		if(y!=p.y) return y<p.y;

                                        		if(z!=p.z)return z<p.z;

                                        		return w<p.w;

                                        		//return x != p.x ? x<p.x: y<p.y;

                                        	}

                                        	bool operator > (const pa4 &p) const{

                                        		if(x!=p.x) return x>p.x;

                                        		if(y!=p.y) return y>p.y;

                                        		if(z!=p.z)return z>p.z;

                                        		return w>p.w;

                                        		//return x != p.x ? x<p.x: y<p.y;

                                        	}

                                        	bool operator == (const pa4 &p) const{

                                        		return x==p.x && y==p.y && z==p.z &&w==p.w;

                                        	}

                                        		

                                        

                                        };

                                        class pa2{

                                        	public:

                                        	int x,y;

                                        	pa2(int x=0,int y=0):x(x),y(y) {}

                                        	pa2 operator + (pa2 p) {return pa2(x+p.x,y+p.y);}

                                        	pa2 operator - (pa2 p) {return pa2(x-p.x,y-p.y);}

                                        	bool operator < (const pa2 &p) const{

                                        		return x != p.x ? x<p.x: y<p.y;

                                        	}

                                        	bool operator > (const pa2 &p) const{

                                        		return x != p.x ? x>p.x: y>p.y;

                                        	}

                                        	bool operator == (const pa2 &p) const{

                                        		return abs(x-p.x)==0 && abs(y-p.y)==0;

                                        	}

                                        	bool operator != (const pa2 &p) const{

                                        		return !(abs(x-p.x)==0 && abs(y-p.y)==0);

                                        	}

                                        		

                                        

                                        };

                                        

                                               #define ppa pair<int,pas>

                                        class Point{

                                        	public:

                                        	double x,y;

                                        	Point(double x=0,double y=0):x(x),y(y) {}

                                        	Point operator + (Point p) {return Point(x+p.x,y+p.y);}

                                        	Point operator - (Point p) {return Point(x-p.x,y-p.y);}

                                        	Point operator * (double a) {return Point(x*a,y*a);}

                                        	Point operator / (double a) {return Point(x/a,y/a);}

                                        	double absv() {return sqrt(norm());}

                                        	double norm() {return x*x+y*y;}

                                        	bool operator < (const Point &p) const{

                                        		return x != p.x ? x<p.x: y<p.y;

                                        	}

                                        	bool operator == (const Point &p) const{

                                        		return fabs(x-p.x)<EPS && fabs(y-p.y)<EPS;

                                        	}

                                        };

                                        typedef Point Vector;

                                 #define pl pair<int,pas>

                                        struct Segment{

                                        Point p1,p2;

                                        };

                                         double dot(Vector a,Vector b){

                                        	return a.x*b.x+a.y*b.y;

                                        }

                                        double cross(Vector a,Vector b){

                                        	return a.x*b.y-a.y*b.x;

                                        }

                                    

            bool parareru(Point a,Point b,Point c,Point d){

            //	if(abs(cross(a-b,d-c))<EPS)cout<<"dd "<<cross(a-b,d-c)<<endl;

            	return abs(cross(a-b,d-c))<EPS;

            }

            double distance_ls_p(Point a, Point b, Point c) {

              if ( dot(b-a, c-a) < EPS ) return (c-a).absv();

              if ( dot(a-b, c-b) < EPS ) return (c-b).absv();

              return abs(cross(b-a, c-a)) / (b-a).absv();

            }

            bool is_intersected_ls(Segment a,Segment b) {

            	if(a.p1==b.p1||a.p2==b.p1||a.p1==b.p2||a.p2==b.p2) return false;

            	if(parareru((a.p2),(a.p1),(a.p1),(b.p2))&&parareru((a.p2),(a.p1),(a.p1),(b.p1))){

            //		cout<<"sss"<<endl;

            		if(dot(a.p1-b.p1,a.p1-b.p2)<EPS) return true;

            		if(dot(a.p2-b.p1,a.p2-b.p2)<EPS) return true;

            		if(dot(a.p1-b.p1,a.p2-b.p1)<EPS) return true;

            		if(dot(a.p1-b.p2,a.p2-b.p2)<EPS) return true;

            		return false;

            	}

              else return ( cross(a.p2-a.p1, b.p1-a.p1) * cross(a.p2-a.p1, b.p2-a.p1) < EPS ) && ( cross(b.p2-b.p1, a.p1-b.p1) * cross(b.p2-b.p1, a.p2-b.p1) < EPS );

            }

             

            double segment_dis(Segment a,Segment b){

            	if(is_intersected_ls(a,b))return 0;

            	double r=distance_ls_p(a.p1, a.p2, b.p1);

            	r=min(r,distance_ls_p(a.p1, a.p2, b.p2));

            	r=min(r,distance_ls_p(b.p1, b.p2, a.p2));

            	r=min(r,distance_ls_p(b.p1, b.p2, a.p1));

            	return r;

            }

            Point intersection_ls(Segment a, Segment b) {

              Point ba = b.p2-b.p1;

              double d1 = abs(cross(ba, a.p1-b.p1));

              double d2 = abs(cross(ba, a.p2-b.p1));

              double t = d1 / (d1 + d2);

             

              return a.p1 + (a.p2-a.p1) * t;

            }

             

                            string itos( int i ) {

                            ostringstream s ;

                            s << i ;

                            return s.str() ;

                            }

                             

                            int gcd(int v,int b){

                            	if(v>b) return gcd(b,v);

                            	if(v==b) return b;

                            	if(b%v==0) return v;

                            	return gcd(v,b%v);

                            }

             

                            double distans(double x1,double y1,double x2,double y2){

                            	double rr=(x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);

                            	return sqrt(rr);

                            	

                            }

                            

   //         int pr[2000010];

     //       int inv[2000010];

            

            int beki(int wa,int rr,int warukazu){

            	if(rr==0) return 1%warukazu;

            	if(rr==1) return wa%warukazu;

            	if(rr%2==1) return (beki(wa,rr-1,warukazu)*wa)%warukazu;

            	int zx=beki(wa,rr/2,warukazu);

            	return (zx*zx)%warukazu;

            }

double bekid(double w,int r){

	if(r==0) return 1.0;

	if(r==1) return w;

	if(r%2) return bekid(w,r-1)*w;

	double f=bekid(w,r/2);

	return f*f;

}

            /*

			int comb(int nn,int rr){

				int r=pr[nn]*inv[rr];

				r%=inf;

				r*=inv[nn-rr];

				r%=inf;

				return r;

			}

            

            void gya(int ert){

            	pr[0]=1;

            	for(int i=1;i<ert;i++){

            		pr[i]=(pr[i-1]*i)%inf;

            	}

            	for(int i=0;i<ert;i++) inv[i]=beki(pr[i],inf-2,inf);

            	

            }

             */

			//priority_queue<pa3,vector<pa3>,greater<pa3>> pq;            

             //sort(ve.begin(),ve.end(),greater<int>());

                                     //----------------kokomade tenpure------------

            //vector<double> ans(100000000),ans2(100000000);

int n;



typedef pair<int,int> P;

struct edge{ int to,cap,cost,rev;};

vector<int> G[100010];

bool used[100010];

int match[100010];

int V;//Vは頂点数



void add_edge(int u,int v){

G[u].push_back(v);

G[v].push_back(u);

}



bool ddffss(int v){

used[v]=true;

  for(int i=0;i<G[v].size();i++){

    int u=G[v][i],w=match[u];

    if(w<0 || !used[w] &&ddffss(w)){

      match[v]=u;

      match[u]=v;

      return true;

    }

  }

  return false;

}



int bi_match(){

  int res=0;

  memset(match,-1,sizeof(match));

  for(int v=0;v<V;v++){

    if(match[v]<0){

      memset(used,0,sizeof(used));

      if(ddffss(v)){

        res++;

      }

    }

  }

  return res;

}



signed main(){

cin>>n;

	int a[110][2],b[110][2];

	

	for(int i=1;i<=n;i++)cin>>a[i][0]>>a[i][1];

	for(int i=1;i<=n;i++)cin>>b[i][0]>>b[i][1];

	V=300;

	for(int i=1;i<=n;i++)for(int j=1;j<=n;j++){

		if(a[i][0]<b[j][0] && a[i][1]<b[j][1]) add_edge(i,105+j);

	

	}

	cout<<bi_match()<<endl;

   	return 0;

        }

// Faster C++ solution for the same problem (measured speedup: 7.430163852783376x):
   #include <bits/stdc++.h>

 

//    #include <boost/multiprecision/cpp_int.hpp>

 #define int long long

 #define inf  1000000007

 #define pa pair<int,int>

 #define ll long long

 #define pal pair<double,double>

 #define ppap pair<pa,int>

  #define PI 3.14159265358979323846

  #define paa pair<int,char>

  #define  mp make_pair

  #define  pb push_back

  #define EPS (1e-10)

                                          

    int dx[8]={0,1,0,-1,1,1,-1,-1};

    int dy[8]={1,0,-1,0,-1,1,1,-1};

                                            using namespace std;

                                   			class pa3{

                                            	public:

                                            	int x;

                                   				int y,z;

                                            	pa3(int x=0,int y=0,int z=0):x(x),y(y),z(z) {}

                                            	bool operator < (const pa3 &p) const{

                                            		if(x!=p.x) return x<p.x;

                                            		if(y!=p.y) return y<p.y;

                                            		 return z<p.z;

                                            		//return x != p.x ? x<p.x: y<p.y;

                                            	}

                                   				bool operator > (const pa3 &p) const{

                                            		if(x!=p.x) return x>p.x;

                                            		if(y!=p.y) return y>p.y;

                                            		 return z>p.z;

                                            		//return x != p.x ? x<p.x: y<p.y;

                                            	}

                                            	bool operator == (const pa3 &p) const{

                                            		return x==p.x && y==p.y && z==p.z;

                                            	}

                                            		bool operator != (const pa3 &p) const{

                                            			return !( x==p.x && y==p.y && z==p.z);

                                            	}

                                            

                                            };

                                            

                                            class pa4{

                                            	public:

                                            	int x;

                                            	int y,z,w;

                                            	pa4(int x=0,int y=0,int z=0,int w=0):x(x),y(y),z(z),w(w) {}

                                            	bool operator < (const pa4 &p) const{

                                            		if(x!=p.x) return x<p.x;

                                            		if(y!=p.y) return y<p.y;

                                            		if(z!=p.z)return z<p.z;

                                            		return w<p.w;

                                            		//return x != p.x ? x<p.x: y<p.y;

                                            	}

                                            	bool operator > (const pa4 &p) const{

                                            		if(x!=p.x) return x>p.x;

                                            		if(y!=p.y) return y>p.y;

                                            		if(z!=p.z)return z>p.z;

                                            		return w>p.w;

                                            		//return x != p.x ? x<p.x: y<p.y;

                                            	}

                                            	bool operator == (const pa4 &p) const{

                                            		return x==p.x && y==p.y && z==p.z &&w==p.w;

                                            	}

                                            		

                                            

                                            };

                                            class pa2{

                                            	public:

                                            	int x,y;

                                            	pa2(int x=0,int y=0):x(x),y(y) {}

                                            	pa2 operator + (pa2 p) {return pa2(x+p.x,y+p.y);}

                                            	pa2 operator - (pa2 p) {return pa2(x-p.x,y-p.y);}

                                            	bool operator < (const pa2 &p) const{

                                            		return y != p.y ? y<p.y: x<p.x;

                                            	}

                                            	bool operator > (const pa2 &p) const{

                                            		return x != p.x ? x<p.x: y<p.y;

                                            	}

                                            	bool operator == (const pa2 &p) const{

                                            		return abs(x-p.x)==0 && abs(y-p.y)==0;

                                            	}

                                            	bool operator != (const pa2 &p) const{

                                            		return !(abs(x-p.x)==0 && abs(y-p.y)==0);

                                            	}

                                            		

                                            

                                            };

                                            

 

                      

                                string itos( int i ) {

                                ostringstream s ;

                                s << i ;

                                return s.str() ;

                                }

                                 

                                int gcd(int v,int b){

                                	if(v>b) return gcd(b,v);

                                	if(v==b) return b;

                                	if(b%v==0) return v;

                                	return gcd(v,b%v);

                                }

                 

                            

                                int mod;

int extgcd(int a, int b, int &x, int &y) {

    if (b == 0) {

        x = 1;

        y = 0;

        return a;

    }

    int d = extgcd(b, a%b, y, x);

    y -= a/b * x;

    return d;

}

pa operator+(const pa & l,const pa & r) {   

    return {l.first+r.first,l.second+r.second};                                    

}    

pa operator-(const pa & l,const pa & r) {   

    return {l.first-r.first,l.second-r.second};                                    

}  

                                

                int pr[200010];

                int inv[200010];

                

                int beki(int wa,int rr,int warukazu){

                	if(rr==0) return 1%warukazu;

                	if(rr==1) return wa%warukazu;

                	wa%=warukazu;

                	if(rr%2==1) return ((ll)beki(wa,rr-1,warukazu)*(ll)wa)%warukazu;

                	ll zx=beki(wa,rr/2,warukazu);

                	return (zx*zx)%warukazu;

                }

 

                

    			int comb(int nn,int rr){

    				if(rr<0 || rr>nn || nn<0) return 0;

    				int r=pr[nn]*inv[rr];

    				r%=mod;

    				r*=inv[nn-rr];

    				r%=mod;

    				return r;

    			}

                

                void gya(int ert){

                	pr[0]=1;

                	for(int i=1;i<=ert;i++){

                		pr[i]=(pr[i-1]*i)%mod;

                	}

                		inv[ert]=beki(pr[ert],mod-2,mod);

                	for(int i=ert-1;i>=0;i--){

                		inv[i]=inv[i+1]*(i+1)%mod;

                	}

                }

                

              //   cin.tie(0);

    		//	ios::sync_with_stdio(false);

    			//priority_queue<pa3,vector<pa3>,greater<pa3>> pq;            

                 //sort(ve.begin(),ve.end(),greater<int>());

//    mt19937(clock_per_sec);

  //  mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count()) ;

      

       

       

                               //----------------kokomade tenpure------------

struct bi_match{

	private:

	public:

	

	// 頂点は0以上V未満

	// 各頂点がどっち側かは意識しなくていい

	// 多重辺はダメ

	

	vector<vector<int>> Graph;

	int V;

	vector<int> match,used;

	bi_match(int V){ // 入力サイズ 

		this->V=V;

		Graph.resize(V);

		match.resize(V,-1);

		used.resize(V,-1);

	}

	

	void add_edge(int u,int v){

		

		Graph[u].pb(v);

		Graph[v].pb(u);		

	}

	

	bool dfs_bi(int v,int num){

		used[v] = num;

  		for(int u:Graph[v]){

    		int w=match[u];

    		if(w<0 || used[w]<num && dfs_bi(w,num)){

      			match[v]=u;

      			match[u]=v;

      			return true;

    		}

  		}

  		return false;

	}

	

	int solve(){

 		int res=0;

  		for(int v=0;v<V;v++){

    		if(match[v]<0){

      			if(dfs_bi(v,v)){

       				 res++;

      			}

    		}

  		}

 		return res;

	}

};



 signed main(){

 	

 

    	       cin.tie(0);

   		ios::sync_with_stdio(false);

int n;

 	cin>>n;

	int a[110][2],b[110][2];

 	

	for(int i=1;i<=n;i++)cin>>a[i][0]>>a[i][1];

	for(int i=1;i<=n;i++)cin>>b[i][0]>>b[i][1];

	int V=300;

	bi_match bi(V);

 	for(int i=1;i<=n;i++)for(int j=1;j<=n;j++){

		if(a[i][0]<b[j][0] && a[i][1]<b[j][1]) bi.add_edge(i,105+j);

	

	}

	cout<<bi.solve()<<endl;



 	return 0;

 	

 }