#include <vector>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <algorithm>
#include <numeric>
#include <sstream>
#include <iostream>
#include <iomanip>
#define _USE_MATH_DEFINES
#include <cmath>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <cfloat>
#include <cmath>
#include <ctime>
#include <cstdio>
#include <cassert>
using namespace std;

#define EPS 1e-12
#define ull unsigned long long
#define ll long long
#define VI vector<ll>
#define PII pair<ll, ll> 
#define VVI vector<vector<ll> >
#define REP(i,n) for(int i=0,_n=(n);(i)<(int)_n;++i)
#define RANGE(i,a,b) for(int i=(int)a,_b=(int)(b);(i)<_b;++i)
#define FOR(i,c) for(__typeof((c).begin())i=(c).begin();i!=(c).end();++i)
#define ALL(c) (c).begin(), (c).end()
#define ALLR(c) (c).rbegin(), (c).rend()
#define PB push_back
#define MP(a, b) make_pair(a, b)
#define POPCOUNT __builtin_popcount
#define POPCOUNTLL __builtin_popcountll
#define CLEAR(table, v) memset(table, v, sizeof(table));
#define PRINT1(table, D0) REP(d0, D0) cout<<table[d0]<<" "; cout<<"\n";
#define PRINT2(table, D0, D1) REP(d0, D0) { REP(d1, D1) cout<<table[d0][d1]<<" "; cout<<"\n"; }
#define PRINT3(table, D0, D1, D2) REP(d0, D0) { REP(d1, D1) { REP(d2, D2) cout<<table[d0][d1][d2]<<" "; cout<<"\n"; } cout<<"\n"; }
#define UNIFORM_DOUBLE(a, b) (((b-a)*(double)rand()/RAND_MAX)+a) // [a, b) 
#define UNIFORM_LL(a, b) (ll)UNIFORM_DOUBLE(a, b) // [a, b) 
#define IN(v, lo, hi) ((lo)<=(v) && (v)<(hi))
#define DD(v) cout<<#v<<": "<<v<<endl
template <typename T0, typename T1> std::ostream& operator<<(std::ostream& os, const map<T0, T1>& v) { for( typename map<T0, T1>::const_iterator p = v.begin(); p!=v.end(); p++ ){os << p->first << ": " << p->second << " ";} return os; }
template <typename T0, typename T1> std::ostream& operator<<(std::ostream& os, const pair<T0, T1>& v) { os << v.first << ": " << v.second << " "; return os; }
template <typename T> std::ostream& operator<<(std::ostream& os, const vector<T>& v) { for( int i = 0; i < (int)v.size(); i++ ) { os << v[i] << " "; } return os; }
template <typename T> std::ostream& operator<<(std::ostream& os, const vector<vector<T> >& v) { for( int i = 0; i < (int)v.size(); i++ ) { os << v[i] << endl; } return os; }
template <typename T> std::ostream& operator<<(std::ostream& os, const set<T>& v) { vector<T> tmp(v.begin(), v.end()); os << tmp; return os; }
template <typename T> std::ostream& operator<<(std::ostream& os, const deque<T>& v) { vector<T> tmp(v.begin(), v.end()); os << tmp; return os; }

#define MOD 1000000007LL
#define INF (1LL<<60)

int main() {
	//ios::sync_with_stdio(false);
	ll N;
	while(cin>>N) {
		VI w(N*3);
		REP(i, N*3) cin>>w[i];
		VI le(N*3), ri(N*3);
		{
			priority_queue<ll, vector<ll>, greater<ll>> q;
			ll sumMaxN = 0;
			// [0, i], [i+1, N*3), i in [0, N*3-2]
			REP(i, N*3-1) {
				ll na = i+1;
				ll nb = N*3-(i+1);
//				DD(na);DD(nb);
				q.push(w[i]);
				sumMaxN += w[i];
				if(na<N || nb<N) continue;
//				DD("ok");
				if(q.size()>N) {
					sumMaxN -= q.top();
					q.pop();
				}
				le[i] = sumMaxN;
			}
		}
		{
			priority_queue<ll> q;
			ll sumMinN = 0;
			// [0, i], [i+1, N*3), i in [0, N*3-2]
			REP(ii, N*3-1) {
				ll i = N*3-2-ii;
				ll na = i+1;
				ll nb = N*3-(i+1);
				q.push(w[i+1]);
				sumMinN += w[i+1];
				if(na<N || nb<N) continue;
				if(q.size()>N) {
					sumMinN -= q.top();
					q.pop();
				}
				ri[i] = sumMinN;
			}
		}
//		DD(le);
//		DD(ri);
		ll ans = -INF;
		REP(i, N*3) {
			ll na = i+1;
			ll nb = N*3-(i+1);
			if(na<N || nb<N) continue;
//			DD(i);
//			DD(le[i]-ri[i]);
			ans = max(ans, le[i]-ri[i]);
		}
		cout<<ans<<endl;
	}
	
	return 0;
}


Measured memory_bytes: 10848