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

int main() {
	int n;
	cin>>n;
	vector<int> males;
	vector<int> females;
	for(int i=0;i<n;i++){
		int height;
		cin>>height;
		males.push_back(height);
	}
	for(int i=0;i<n;i++){
		int height;
		cin>>height;
		females.push_back(height);
	}
	int pairs=0;
	vector<int> positiveMales;
	vector<int> positiveFemales;
	vector<int> negativeMales;
	vector<int> negativeFemales;
	
	for(int i=0;i<n;i++){
		if(males[i]<0)
			negativeMales.push_back(abs(males[i]));
		else
			positiveMales.push_back(males[i]);
	}
	for(int i=0;i<n;i++){
		if(females[i]<0)
			negativeFemales.push_back(abs(females[i]));
		else
			positiveFemales.push_back(females[i]);
	}
	sort(negativeMales.begin(), negativeMales.end());
	sort(positiveMales.begin(), positiveMales.end());
	sort(negativeFemales.begin(), negativeFemales.end());
	sort(positiveFemales.begin(), positiveFemales.end());
	int i=0, j=0;
	while(i<positiveMales.size() && j<negativeFemales.size()){
		if(positiveMales[i]<negativeFemales[j]){
			pairs++;
			i++;
			j++;
		}
		else{
			j++;
		}
	}
	i=0, j=0;
	while(i<positiveFemales.size() && j<negativeMales.size()){
		if(positiveFemales[i]<negativeMales[j]){
			pairs++;
			i++;
			j++;
		}
		else{
			j++;
		}
	}
	cout<<pairs;
	return 0;
}