Submission #1194567

#	Time	Username	Problem	Language	Result	Execution time	Memory
1194567		aykhn	Message (IOI24_message)	C++20	72.85 / 100	439 ms	884 KiB

message

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

using namespace std;

const int B = 1, REV = 1;
const int SEED = 18681;

mt19937 rng;

int o[(1 << 5)][31];
  
  // int o[31] = {9, 17, 7, 27, 10, 22, 21, 6, 30, 3, 24, 15, 29, 19, 2, 13, 23, 20, 14, 1, 25, 5, 4, 8, 0, 16, 18, 28, 11, 12, 26};
  
int calc(vector<bool> C, int k)
{
  int res = 0;
  vector<int> unlock;
  for (int i = 0; i < 31 && unlock.size() < 16;)
  {
    if (31 - i == 16 - (int)unlock.size())
    {
      for (int j = i; j < 31; j++) unlock.push_back(o[k][j]);
      break;
    }
    vector<bool> v(31, 0);
    int j = 0;
    while (i < 31 && j < unlock.size())
    {
      if (C[o[k][i]] == 0) v[unlock[j]] = 1, unlock.push_back(o[k][i]);
      else v[unlock[j]] = 0;
      i++, j++;
    }
    if ((31 - i) < (16 - (int)unlock.size()) * 2)
    {
      for (int l = i; l < 31; l++) v[o[k][l]] = (C[o[k][i]] == 0);
      if (C[o[k][i]] == 0) unlock.push_back(o[k][i]);
      i++;
    }
    res++;
  }
  return res;
}

void send_message(vector<bool> M, vector<bool> C) 
{
  rng = mt19937(SEED);
  for (int i = 0; i < (1 << B); i++)
  {
    for (int j = 0; j < 31; j++)
    {
      o[i][j] = rng() % (j + 1);
      for (int k = 0; k < j; k++) 
      {
        if (o[i][k] >= o[i][j]) o[i][k]++;
      }
    }
  }
  if (REV)
  {
    for (int i = 0; i < (1 << B); i++)
    {
      for (int j = 0; j < 31; j++)
      {
        o[i + (1 << B)][j] = o[i][j];
      }
      reverse(o[i + (1 << B)], o[i + (1 << B)] + 31);
    }
  }
  int n = M.size();
  int cost[(1 << (B + REV))];
  for (int i = 0; i < (1 << (B + REV)); i++) cost[i] = calc(C, i);
  int k = min_element(cost, cost + (1 << (B + REV))) - cost;
  for (int i = 0; i < B + REV; i++) send_packet(vector<bool>(31, k >> i & 1));
  vector<int> unlock;
  for (int i = 0; i < 31 && unlock.size() < 16;)
  {
    if (31 - i == 16 - (int)unlock.size())
    {
      for (int j = i; j < 31; j++) unlock.push_back(o[k][j]);
      break;
    }
    vector<bool> v(31, 0);
    int j = 0;
    while (i < 31 && j < unlock.size())
    {
      if (C[o[k][i]] == 0) v[unlock[j]] = 1, unlock.push_back(o[k][i]);
      else v[unlock[j]] = 0;
      i++, j++;
    }
    if ((31 - i) < (16 - (int)unlock.size()) * 2)
    {
      for (int l = i; l < 31; l++) v[o[k][l]] = (C[o[k][i]] == 0);
      if (C[o[k][i]] == 0) unlock.push_back(o[k][i]);
      i++;
    }
    send_packet(v);
  }
  {
    vector<bool> v(31, 0);
    for (int i = 0; i <= 10; i++) v[unlock[i]] = (n >> i & 1);
    send_packet(v);
  }
  for (int i = 0; i < (n + 15) / 16; i++)
  {
    vector<bool> v(31, 0);
    for (int j = 0; j < 16; j++)
    {
      if (i * 16 + j >= n) break;
      v[unlock[j]] = M[i * 16 + j];
    }
    send_packet(v);
  }
}

vector<bool> receive_message(vector<vector<bool>> R) 
{
  rng = mt19937(SEED);
  for (int i = 0; i < (1 << B); i++)
  {
    for (int j = 0; j < 31; j++)
    {
      o[i][j] = rng() % (j + 1);
      for (int k = 0; k < j; k++) 
      {
        if (o[i][k] >= o[i][j]) o[i][k]++;
      }
    }
  }
  if (REV)
  {
    for (int i = 0; i < (1 << B); i++)
    {
      for (int j = 0; j < 31; j++)
      {
        o[i + (1 << B)][j] = o[i][j];
      }
      reverse(o[i + (1 << B)], o[i + (1 << B)] + 31);
    }
  }
  vector<int> unlock;
  int cur = -1;
  auto nxt = [&]()
  {
    return R[++cur];
  };
  auto get = [&](vector<bool> A)
  {
    int cnt = 0;
    for (auto i : A) cnt += (int)i;
    return cnt >= 16;
  };
  int k = 0;
  for (int i = 0; i < (B + REV); i++) k |= (get(nxt()) << i);
  for (int i = 0; i < 31 && unlock.size() < 16;)
  {
    if (31 - i == 16 - (int)unlock.size())
    {
      for (int j = i; j < 31; j++) unlock.push_back(o[k][j]);
      break;
    }
    vector<bool> v = nxt();
    int j = 0;
    while (i < 31 && j < unlock.size())
    {
      if (v[unlock[j]] == 1) unlock.push_back(o[k][i]);
      i++, j++;
    }
    vector<int> un(31, 0);
    for (int j : unlock) un[j] = 1;
    if ((31 - i) < (16 - (int)unlock.size()) * 2)
    {
      int cnt = 0;
      for (int l = i; l < 31; l++) cnt += (int)v[o[k][l]];
      if (cnt >= (16 - (int)unlock.size())) unlock.push_back(o[k][i]);
      i++;
    }
  }
  vector<bool> sz = nxt();
  int n = 0;
  for (int i = 0; i <= 10; i++) 
  {
    if (sz[unlock[i]]) n |= (1 << i);
  }
  vector<bool> res(n, 0);
  for (int i = 0; i < (n + 15) / 16; i++)
  {
    vector<bool> v = nxt();
    for (int j = 0; j < 16; j++)
    {
      if (i * 16 + j >= n) break;
      res[i * 16 + j] = v[unlock[j]];
    }
  }
  return res;
}

• Subtask 0: 0 / 0
• Subtask 1: 10 / 10
• Subtask 2: 62.8504 / 90