Cod sursă (job #446087)

#include <bits/stdc++.h>
using namespace std;

int n;
list<int> q;
priority_queue <int, vector<int>, greater<int> > pq;

int main()
{
	ifstream cin("lanterna.in");
	ofstream cout("lanterna.out");
	cin >> n;
	for (int i = 1; i <= n; i++)
	{
		int x;
		cin >> x;
		q.push_back(x);
	}
	q.sort();
	long long s = q.front();
	pq.push(q.front());
	q.pop_front();
	s += q.front();
	pq.push(q.front());
	q.pop_front();
	q.push_front(pq.top());
	pq.pop();
	while(!q.empty())
	{
		int last1 = q.back();
		q.pop_back();
		int firsts = q.front();
		q.pop_front();
		int firstf = pq.top();
		pq.pop();
		if (q.empty())
		{
			s += last1;
			break;
		}
		int last2 = q.back();
		q.pop_back();
		if (last1 + firstf < last1 + 2 * firsts + last2)
		{
			s += last1 + firstf;
			pq.push(last1);
			pq.push(last2);
			q.push_front(firstf);
			q.push_front(firsts);
		}
		else
		{
			s += last1 + last2 + 2 * firsts;
			pq.push(last1);
			pq.push(last2);
			pq.push(firstf);
			q.push_front(firsts);
		}
	}
	cout << s;
}