#include <bits/stdc++.h>
using namespace std;
#define ll long long
const int maxn = 2020;
int a[maxn], b[maxn];
ll sb[maxn], dp[maxn][maxn];
int main(void) {
    //freopen("g.in","r",stdin);
    int T; scanf("%d",&T);
    while (T--) {
        int n; 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]);
        for (int i=1;i<=n;i++) sb[i]=sb[i-1]+b[i];
        memset(dp,0x3f,sizeof(dp));
        dp[0][0]=0;
        for (int i=1;i<=n;i++) {
            for (int j=0;j<=i;j++) {
                dp[i][j]=dp[i-1][j];
                if (j>0 && dp[i-1][j-1]+a[i] <= sb[i]) {
                    dp[i][j] = min(dp[i][j], dp[i-1][j-1]+a[i]);
                }
            }
        }
        int ans = 0;
        for (int i=0;i<=n;i++) if (dp[n][i]<=1e18) ans=i;
        printf("%d\n",ans);
    }
    return 0;
}