#include <bits/stdc++.h> using namespace std; #define int long long signed main() { ios::sync_with_stdio(0); cin.tie(0); int T; cin >> T; while (T--) { int n; cin >> n; vector<int> a(n), b(n); for (int i=0;i<n;i++) cin>>a[i]; for (int i=0;i<n;i++) cin>>b[i]; sort(a.begin(),a.end()); sort(b.begin(),b.end()); reverse(b.begin(),b.end()); int ans=1e18; for(int i=0;i<n;i++) ans=min(ans,abs(a[i]-b[i])); cout<<ans<<'\n'; } return 0; }