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

int main() {
    #ifdef _DEBUG
    	freopen("input.txt", "r", stdin);
    //	freopen("output.txt", "w", stdout);
    #endif

	int n;
	cin >> n;
	vector<int> A(n), B(n);
	for (auto &it : A) cin >> it;
	for (auto &it : B) cin >> it;
	vector<int> C(n);
	for(int i=0;i<n;i++)
	{
	    C[i] = A[i]-B[i];
	}
	long long ans=0;
    sort(C.begin(),C.end());
    for(int i=0;i<n;i++)
    {
        if(C[i] <=0) continue;
        int y =lower_bound(C.begin(), C.end(), (1-C[i]))-C.begin();
        ans+=i-y;
    }
	cout << ans << endl;
	return 0;
}