#include <bits/stdc++.h>
using namespace std;
int t, n;
long long f[2010][2010];
int a[2010], b[2010];
int main() {
    scanf("%d", &t);
    while (t--) {
        scanf("%d", &n);
        for (int i = 1; i <= n; ++i) scanf("%d", &a[i]);
        for (int i = 1; i <= n; ++i) scanf("%d", &b[i]);
        memset(f, 0x3f, sizeof f);
        f[0][0] = 0;
        long long sum = 0;
        for (int i = 1; i <= n; ++i) {
            sum += b[i];
            for (int j = 0; j <= n; ++j) {
                f[i][j] = min(f[i][j], f[i - 1][j]);
                if (j && f[i - 1][j - 1] + a[i] <= sum)
                    f[i][j] = min(f[i][j], f[i - 1][j - 1] + a[i]);
            }
        }
        int ans = 0;
        for (int i = 1; i <= n; ++i)
            if (f[n][i] <= sum) ans = i;
        printf("%d\n", ans);
    }
}