Submission #1035366

#	Time	Username	Problem	Language	Result	Execution time	Memory
1035366		Boas	Carnival Tickets (IOI20_tickets)	C++17	100 / 100	586 ms	76216 KiB

tickets

#include "tickets.h"

#include <bits/stdc++.h>
using namespace std;
#define loop(x, i) for (int i = 0; i < (x); i++)
#define ALL(x) (x).begin(), x.end()
#define pb push_back
#define int long long
typedef pair<int, int> ii;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<signed> vi32;
typedef vector<bool> vb;
typedef set<int> si;
typedef vector<vi> vvi;
typedef vector<vi32> vvi32;
typedef vector<si> vsi;
typedef vector<ii> vii;
typedef set<iii> siii;

int find_maximum(signed k, vvi32 x)
{
	int n = x.size();
	int m = x[0].size();
	vvi32 answer(n, vi32(m, -1));
	vi firstFree(n, k), lastFree(n, m - 1);
	priority_queue<ii> switches;
	loop(n, i)
	{
		switches.push({x[i][firstFree[i] - 1] + x[i][lastFree[i]], i});
	}
	loop(k * n / 2, iter)
	{
		if (switches.empty())
			break;
		auto [v, i] = switches.top();
		switches.pop();
		firstFree[i]--;
		lastFree[i]--;
		if (firstFree[i] > 0)
			switches.push({x[i][firstFree[i] - 1] + x[i][lastFree[i]], i});
	}
	int res = 0;
	loop(k, round)
	{
		vi a;
		vii plusPerPile;
		loop(n, i)
		{
			plusPerPile.pb({m - 1 - lastFree[i], i});
		}
		sort(ALL(plusPerPile));
		for (int ix = 0; ix < n; ix++)
		{
			auto &[cnt, i] = plusPerPile[ix];
			if (ix >= n / 2)
			{
				lastFree[i]++;
				answer[i][lastFree[i]] = round;
				a.pb(x[i][lastFree[i]]);
			}
			else
			{
				firstFree[i]--;
				answer[i][firstFree[i]] = round;
				a.pb(x[i][firstFree[i]]);
			}
		}
		sort(ALL(a));
		int b = a[n / 2];
		for (int v : a)
			res += abs(v - b);
	}
	allocate_tickets(answer);
	return res;
}

• Subtask 1: 11 / 11
• Subtask 2: 16 / 16
• Subtask 3: 14 / 14
• Subtask 4: 14 / 14
• Subtask 5: 12 / 12
• Subtask 6: 23 / 23
• Subtask 7: 10 / 10