#include <iostream>
#include<bits/stdc++.h>

using namespace std;

int main() {
	// your code goes here
	int n;
	cin>>n;
	vector<int> m(n+1);
	vector<int> f(n+1);
	vector<int> p1;
	vector<int> p2;
	vector<int> p3;
	vector<int> p4;
	

	
	for(int i=0;i<n;i++){
		cin>>m[i];
		if(m[i]>=0){
			p1.push_back(m[i]);
		}
		else{
			p2.push_back(-m[i]);
		}
	}
	
	for(int i=0;i<n;i++){
		cin>>f[i];
		if(f[i]>=0){
			p3.push_back(f[i]);
		}
		else{
			p4.push_back(-f[i]);
		}
	} 
	
	sort(p1.begin(),p1.end());
	sort(p2.begin(),p2.end());
	sort(p3.begin(),p3.end());
	sort(p4.begin(),p4.end());
	
	int i=0;
	int j=0;
	int cnt=0;
	
		while(i<p1.size() && j<p4.size()){
			if(p4[j]>p1[i]){
				cnt++;
				i++;
				j++;
				
			}
			else if(p4[j]<=p1[i]){
				j++;
			}
		}
		
		i = 0;
		j=0;
		
		while(i<p2.size() && j<p3.size()){
			if(p2[i]>p3[j]){
				cnt++;
				i++;
				j++;
				
			}
			else if(p2[i]<=p3[j]){
				i++;
			}
		}
		
		cout<<cnt;
		
		
		
		
	
	return 0;
}