#pragma clang diagnostic push
#pragma ide diagnostic ignored "cert-err34-c"
#include <bits/stdc++.h>

using namespace std;

int n, z = 2, q = 1;
int i, a, nu;

struct zona
{
	int a1;
	int a2;
};

zona v[1002];
bool test (zona x, zona b)
{
	return (x.a2 < b.a2);
}

int main()
{
	freopen ("eoliene.in", "r", stdin);
	freopen ("eoliene.out", "w", stdout);
	cin >> n;

	for (i = 1; i <= n; ++i)
		cin >> v[i].a1;

	for (i = 1; i <= n; ++i)
	{
		cin >> v[i].a2;
		a = v[i].a2;
		v[i].a2 = v[i].a2 + v[i].a1;
		v[i].a1 = v[i].a1 - a;
	}

	sort (v + 1, v + n + 1, test);

	while (z <= n)
	{
		if (v[z].a1 <= v[q].a2)
			++nu;
		else
			q = z;

		++z;
	}

	cout << nu << '\n';
	return 0;
}
#pragma clang diagnostic pop