Submission #305651

#	Time	Username	Problem	Language	Result	Execution time	Memory
305651		Lawliet	Carnival Tickets (IOI20_tickets)	C++14	100 / 100	1145 ms	92820 KiB

tickets

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

using namespace std;
typedef long long int lli;
typedef pair<int,int> pii;

const int MAXN = 1510;

int pL[MAXN], pR[MAXN];
int qtd[MAXN], ord[MAXN];

bool cmp(int i, int j) { return qtd[i] > qtd[j]; }

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

	vector< vector<int> > answer;

	for(int i = 0; i < n; i++) 
		answer.push_back( vector<int>( m , -1 ) );

	lli ans = 0;
	vector< pair<lli,int> > sum;

	for(int i = 0 ; i < n ; i++)
	{
		qtd[i] = k;

		for(int j = 0 ; j < k ; j++)
		{
			ans -= x[i][j];
			sum.push_back( { x[i][j] + x[i][m - k + j] , i } );
		}
	}

	sort( sum.begin() , sum.end() );
	reverse( sum.begin() , sum.end() );

	for(int i = 0 ; i < (n/2)*k ; i++)
	{
		ans += sum[i].first;
		qtd[ sum[i].second ]--;
	}

	iota( ord , ord + n , 0 );

	for(int i = 0 ; i < n ; i++)
		pL[i] = 0, pR[i] = m - 1;

	for(int t = 0 ; t < k ; t++)
	{
		sort( ord , ord + n , cmp );

		for(int i = 0 ; i < n/2 ; i++)
			answer[ ord[i] ][ pL[ ord[i] ]++ ] = t, qtd[ ord[i] ]--;

		for(int i = n/2 ; i < n ; i++)
			answer[ ord[i] ][ pR[ ord[i] ]-- ] = t;
	}

	allocate_tickets( answer );

	return ans;
}

• 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