#include <bits/stdc++.h>

using namespace std;

int T, n, ans, a[2010];
long long b[2010], f[2010][2010];

int main() {
  scanf("%d", &T);
  while (T--) {
    memset(f, -1, sizeof(f));
    scanf("%d", &n);
    for (int i = 1; i <= n; ++i) scanf("%d", &a[i]);
    for (int i = 1; i <= n; ++i) {
      scanf("%lld", &b[i]);
      b[i] += b[i - 1];
    }
    f[0][0] = ans = 0;
    for (int i = 1; i <= n; ++i) {
      f[i][0] = 0;
      for (int j = 1; j <= i; ++j) {
        f[i][j] = f[i - 1][j];
        if (f[i - 1][j - 1] != -1 && f[i - 1][j - 1] + a[i] <= b[i])
          if (f[i][j] == -1 || f[i - 1][j - 1] + a[i] <= f[i][j])
            f[i][j] = f[i - 1][j - 1] + a[i];
        if (f[i][j] != -1) ans = max(ans, j);
      }
    }
    printf("%d\n", ans);
  }
  return 0;
}