Submission #580472

#	Time	Username	Problem	Language	Result	Execution time	Memory
580472		joelau	Carnival Tickets (IOI20_tickets)	C++14	25 / 100	897 ms	146668 KiB

tickets

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

long long A[1505][1505], B[1505], C[1505];
vector< tuple<long long,long long,long long> > lst;
bitset<1505> bs;

long long find_maximum(int k, vector<vector<int>> x) {
	long long N = x.size(), M = x[0].size();
	for (long long i = 0; i < N; ++i) for (long long j = 0; j < M; ++j) lst.emplace_back(x[i][j],i,j);
	sort(lst.begin(),lst.end());
	memset(A,0,sizeof(A));
	for (long long i = 0; i < N*M/2; ++i) A[get<1>(lst[i])][get<2>(lst[i])] = 1;
	memset(B,0,sizeof(B)); memset(C,0,sizeof(C));
	for (long long i = 0; i < N; ++i) {
		while (C[i] < M && A[i][C[i]] == 1) C[i]++;
	}
	long long val = 0;
	vector< vector<int> > ans (N, vector<int>(M,-1));
	for (long long j = 0; j < M; ++j) {
		bs.reset();
		long long cnt = 0;
		for (long long i = 0; i < N; ++i) {
			if (B[i] == M || A[i][B[i]] == 0) ans[i][C[i]] = j, val += x[i][C[i]], C[i]++, bs[i] = 1;
			else if (C[i] == M) ans[i][B[i]] = j, cnt++, val -= x[i][B[i]], B[i]++, bs[i] = 1;
		}
		for (long long i = 0; i < N; ++i) if (!bs[i]) {
			if (cnt < N/2 && A[i][B[i]] == 1) ans[i][B[i]] = j, cnt++, val -= x[i][B[i]], B[i]++;
			else ans[i][C[i]] = j, val += x[i][C[i]], C[i]++;
		}
	}
	allocate_tickets(ans);
	return val;
}

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