/*                        I am not the best, but I am better than your father.                                          */
#include <bits/stdc++.h>
using namespace std;
using ll=long long ;
#define len(s) (int)s.size()
#define ss second
#define ff first
#define all(a) a.begin(),a.end()
#define s(a,b) for ( int i = a ; i < b ; i++)
#define q(a,b) for ( int j = a ; j < b ; j++)
void solve ()
{
 int n , m ;
 cin >>n >> m;
 int  arr[m];
 arr[0]=1;
 s(1,n+1)
 arr[i]=i*arr[i-1];
 cout<< arr[n]/(arr[m]*arr[n-m])<<endl;
}
void solve2()
{
    int n;
     cin>>n;
     int arr[n], arr1[n];
     s(0,n)
     cin>>arr[i];
     s(0,n)
     cin>>arr1[i];
     int ma= 0;
     s(0,n)
     {
         if(arr1[i]>arr[i])
         {
         int z =arr1[i]-arr[i];
         ma=max(ma,z);
     }}
     cout<<ma<<"\n";
}
int main() {
  // solve();
  ll t;
  cin >> t;
  while(t--){
      solve2();
  }
}