#include<bits/stdc++.h>
#define ll long long
using namespace std;
int T,n;
ll dp[2005][2005],a[2005],b[2005];

int read(){
    int x=0;char ch=getchar();
    while(!isdigit(ch)) ch=getchar();
    while(isdigit(ch)) x=(x<<3)+(x<<1)+(ch^48),ch=getchar();
    return x;
}

void print(ll x){
    if(x>=10) print(x/10);
    putchar(x%10+'0');
}

int main(){
    T=read();
    while(T--){
        n=read();
        for(int i=0;i<=n;i++){
            for(int j=0;j<=n;j++) dp[i][j]=1e18;
        }
        for(int i=1;i<=n;i++) a[i]=read();
        for(int i=1;i<=n;i++) b[i]=read(),b[i]+=b[i-1];
        dp[0][0]=0;
        for(int i=1;i<=n;i++){
            for(int j=0;j<=i;j++){
                dp[i][j]=min(dp[i][j],dp[i-1][j]);
                if(j){
                    if(dp[i-1][j-1]+a[i]<=b[i]) dp[i][j]=min(dp[i][j],dp[i-1][j-1]+a[i]);
                }
            }
        }
        for(int i=n;i>=0;i--){
            if(dp[n][i]!=1e18){
                print(i),puts("");
                break;
            }
        }
    }

    return 0;
}