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

typedef long long int ll;
typedef vector<ll> vl;

void solve()
{
ll i, j, n, cnt = 0;
cin >> n;
vl A(n), B(n), C(n);
for (i = 0; i < n; i++)
{
cin >> A[i];
}
for (i = 0; i < n; i++)
{
cin >> B[i];
}
for (i = 0; i < n; i++)
{
C[i] = A[i] - B[i];
}
// since addition is commutative just sort the elements of the array C
sort(C.begin(), C.end());
for (i = 0; i < n; i++)
{
if (C[i] <= 0)
{
// we want to find element Cj which is strictly greater than -Ci
// Cj>-Ci equivalent to finding a  Cj>=-Ci+1
if (lower_bound(C.begin(), C.end(), -C[i] + 1ll) - C.begin() != n)
{
cnt += n - (lower_bound(C.begin(), C.end(), -C[i] + 1ll) - C.begin());
}
}
else
{
cnt += n - (i + 1);
}
}
cout << cnt << endl;
}

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

ios_base::sync_with_stdio(false);
cin.tie(NULL);
int i, T;

T = 1;
cin >> T;

for (i = 1; i <= T; i++)
{
solve();
}
return 0;
}```