#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N = 2005;
int n;
LL a[N], b[N], f[N][N]; // alice problem = 1..i, pts = j, Min(Time)
void solve() {
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= n; i++) cin >> b[i], b[i] += b[i - 1];
    memset(f, 0x3f, sizeof f);
    f[0][0] = 0;
    int ans = 0;
    for (int i = 1; i <= n; i++)
        for (int j = 0; j <= i; j++) {
            f[i][j] = f[i - 1][j];
            if (j && f[i - 1][j - 1] + a[i] <= b[i])
                f[i][j] = min(f[i][j], f[i - 1][j - 1] + a[i]);
            if (f[i][j] != f[0][1]) ans = max(ans, j);
        }
    cout << ans << endl;
}
int main() {
    int T;
    cin >> T;
    while (T--) {
        solve();
    }
    return 0;
}