#include <bits/stdc++.h> // #define int long long #define fst first #define sec second #define pb push_back using namespace std; int t,n; int a[5005],b[5005]; void slv(){ cin>>n; for (int i=1;i<=n;i++){ cin>>a[i]; } for (int i=1;i<=n;i++){ cin>>b[i]; } sort(a+1,a+n+1); sort(b+1,b+n+1); int ans=0; int minn=2000000000; for (int i=1;i<n;i++){ minn=2000000000; for (int j=1;j<=n-i;j++){ minn=min(minn,abs(a[j]-b[j+i])); } for (int j=n-i+1;j<=n;j++){ int np=j-(n-i); minn=min(minn,abs(a[j]-b[np])); } ans=max(ans,minn); } cout<<ans<<'\n'; return ; } signed main(){ // freopen("test.in","r",stdin); // freopen("test.out","w",stdout); ios::sync_with_stdio(0); cin.tie(0);cout.tie(0); cin>>t; while (t--){ slv(); } cout.flush(); return 0; }