#include<bits/stdc++.h>
using namespace std;
inline int read()
{
	char ch=getchar();int x=0,f=1;
	while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
	while(ch>='0'&&ch<='9'){x=x*10-48+ch;ch=getchar();}
	return x*f;
}
const int maxn=5005;
int n,b[maxn],a[maxn];
int f[maxn][maxn];
bool cmp(int a,int b)
{
	return a>b;
}
int main()
{
	freopen("horsea.in","r",stdin);
	freopen("horsea.out","w",stdout);
	n=read();
	for(int i=1;i<=n;i++)a[i]=read();
	for(int i=1;i<=n;i++)b[i]=read();
	sort(b+1,b+n+1,cmp);
	sort(a+1,a+n+1,cmp);
	for(int i=1;i<=n;i++)
	for(int j=1;j<=n;j++)
	{
		if(b[i]>a[j])f[i][j]=max(f[i-1][j-1]+1,max(f[i-1][j]-1,f[i][j-1]-1));
		else if(b[i]==a[j])f[i][j]=max(f[i-1][j-1],max(f[i-1][j]-1,f[i][j-1]-1));
		else f[i][j]=max(f[i-1][j]-1,f[i][j-1]-1);
	}
	cout<<f[n][n];
	return 0;
}