Submission #301079

#	Time	Username	Problem	Language	Result	Execution time	Memory
301079		luciocf	Carnival Tickets (IOI20_tickets)	C++14	41 / 100	764 ms	62200 KiB

tickets

#include <bits/stdc++.h>
#include "tickets.h"

using namespace std;

typedef long long ll;

const int maxn = 1510;

int turno[maxn][maxn];
int ord[maxn];

int qtd[maxn];

int ptr_l[maxn], ptr_r[maxn];

ll find_maximum(int k, vector<vector<int>> x)
{
	int n = x.size();
	int m = x[0].size();

	if (k == 1)
	{
		for (int i = 0; i < n; i++)
		{
			memset(turno[i], -1, sizeof turno[i]);
			ord[i] = i;
		}

		sort(ord, ord+n, [&] (int a, int b) {return x[a][0]+x[a][m-1] > x[b][0]+x[b][m-1];});

		ll ans = 0;

		for (int i = 0; i < n/2; i++)
		{
			turno[ord[i]][m-1] = 0;
			ans += 1ll*x[ord[i]][m-1];
		}

		for (int i = n/2; i < n; i++)
		{
			turno[ord[i]][0] = 0;
			ans -= 1ll*x[ord[i]][0];
		}

		vector<vector<int>> S;
			
		for (int i = 0; i < n; i++)
		{
			vector<int> y;
			y.resize(m);
			
			for (int j = 0; j < m; j++)
				y[j] = turno[i][j];

			S.push_back(y);
		}

		allocate_tickets(S);
		return ans;
	}

	for (int i = 0; i < n; i++)
	{
		memset(turno[i], -1, sizeof turno[i]);
		ord[i] = i, ptr_l[i] = 0, ptr_r[i] = m-1;
 
		for (int j = 0; j < m; j++)
			if (x[i][j] == 0)
				qtd[i]++;
	}
 
	ll ans = 0;
 
	for (int r = 0; r < k; r++)
	{
		sort(ord, ord+n, [&] (int a, int b) {return qtd[a] > qtd[b];});
 
		int tot[2];
		tot[0] = 0, tot[1] = 0;
 
		for (int i = 0; i < n/2; i++)
		{
			int j = ord[i];
 
			turno[j][ptr_l[j]] = r;
			tot[x[j][ptr_l[j]]]++;
 
			if (x[j][ptr_l[j]] == 0) qtd[j]--;
 
			ptr_l[j]++;
		}
 
		for (int i = n/2; i < n; i++)
		{
			int j = ord[i];
 
			turno[j][ptr_r[j]] = r;
			tot[x[j][ptr_r[j]]]++;
 
			if (x[j][ptr_r[j]] == 0) qtd[j]--;
 
			ptr_r[j]--;
		}
 
		ans += 1ll*min(tot[0], tot[1]);
	}
 
	vector<vector<int>> S;
		
	for (int i = 0; i < n; i++)
	{
		vector<int> y;
		y.resize(m);
		
		for (int j = 0; j < m; j++)
			y[j] = turno[i][j];
 
		S.push_back(y);
	}
 
	allocate_tickets(S);
	return ans;
}

• Subtask 1: 11 / 11
• Subtask 2: 16 / 16
• Subtask 3: 14 / 14
• Subtask 4: 0 / 14
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23
• Subtask 7: 0 / 10