Problem:
Score : 500 points

Problem Statement

Let N be a positive integer.

There is a numerical sequence of length 3N, a = (a_1, a_2, ..., a_{3N}).
Snuke is constructing a new sequence of length 2N, a', by removing exactly N elements from a without changing the order of the remaining elements.
Here, the score of a' is defined as follows: (the sum of the elements in the first half of a') - (the sum of the elements in the second half of a').

Find the maximum possible score of a'.

Constraints

1 ≤ N ≤ 10^5

a_i is an integer.

1 ≤ a_i ≤ 10^9

Partial Score

In the test set worth 300 points, N ≤ 1000.

Input

Input is given from Standard Input in the following format:

N
a_1 a_2 ... a_{3N}

Output

Print the maximum possible score of a'.

Sample Input 1

2
3 1 4 1 5 9

Sample Output 1

1

When a_2 and a_6 are removed, a' will be (3, 4, 1, 5), which has a score of (3 + 4) - (1 + 5) = 1.

Sample Input 2

1
1 2 3

Sample Output 2

-1

For example, when a_1 are removed, a' will be (2, 3), which has a score of 2 - 3 = -1.

Sample Input 3

3
8 2 2 7 4 6 5 3 8

Sample Output 3

5

For example, when a_2, a_3 and a_9 are removed, a' will be (8, 7, 4, 6, 5, 3), which has a score of (8 + 7 + 4) - (6 + 5 + 3) = 5.

Solution in C++14 (GCC 5.4.1) (judge verdict: Time Limit Exceeded)

#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define rep(i,n) for (int i=0;i<(n);i++)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)

#define inf INT_MAX/3
#define INF INT_MAX/3
#define PB push_back
#define pb push_back
#define MP make_pair
#define mp make_pair
#define ALL(a) (a).begin(),(a).end()
#define all(a) (a).begin(),(a).end()
#define SET(a,c) memset(a,c,sizeof a)
#define CLR(a) memset(a,0,sizeof a)
#define PII pair<int,int>
#define pii pair<int,int>
#define pcc pair<char,char>
#define pic pair<int,char>
#define pci pair<char,int>
#define VS vector<string>
#define VI vector<int>
#define debug(x) cout<<#x<<": "<<x<<endl
#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define MIN(a,b) (a>b?b:a)
#define MAX(a,b) (a>b?a:b)
#define pi 2*acos(0.0)
#define INFILE() freopen("in0.txt","r",stdin)
#define OUTFILE()freopen("out0.txt","w",stdout)
#define in scanf
#define out printf
#define LL long long
#define ll long long
#define ULL unsigned long long
#define ull unsigned long long
#define eps 1e-14
#define FST first
#define SEC second

#define sint(x) int x; scanf("%d",&x);
#define sint2(x,y) int x,y; scanf("%d %d",&x,&y);
#define lint(x) long long x; scanf("%lld",&x);
#define vint(v,n) vector<int> v(n); rep(i,n) scanf("%d", &v[i]);
#define vlint(v,n) vector<lint> v(n); rep(i,n) scanf("%lld", &v[i]);
#define sdouble(x) double x; scanf("%lf",&x);
#define vdouble(v,n) vector<double> v(n); rep(i,n) scanf("%lf", &v[i]);
#define schar(x) char x; scanf(" %c", &x);
#define sstring(x) string x; cin >> x;

#ifdef _MSC_VER
#define _CRT_SECURE_NO_WARNINGS
#endif

#include <stdio.h>
#include <cstdio>
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <numeric>
#include <climits>
using namespace std;



int main(int argc, char** argv) {
	sint(N);
	vint(a, 3 * N);

	vector<int> left(N), middle(N), right(2 * N);
	copy(a.begin(), a.begin() + N, left.begin());
	copy(a.begin() + N, a.begin() + 2 * N, middle.begin());
	copy(a.begin() + N, a.end(), right.begin());
	sort(all(left));
	sort(all(right));

	ll leftSum = accumulate(all(left), (ll)0);
	ll rightSum = accumulate(right.begin(), right.begin() + N, (ll)0);
	ll min = leftSum - rightSum;
	rep(i, N) {
		int m = middle[i];
		if (m > left[0]) {
			left.erase(left.begin());
			left.insert(lower_bound(all(left), m), m);
			leftSum = accumulate(all(left), (ll)0);
		}
		right.erase(find(all(right), m));
		if (m < right[N - 1]) {
			rightSum = accumulate(right.begin(), right.begin() + N, (ll)0);
		}
		ll score = leftSum - rightSum;
		if (min < score) {
			min = score;
		}
	}
	printf("%lld\n", min);
}