Submission #836904

#	Time	Username	Problem	Language	Result	Execution time	Memory
836904		Johann	Prisoner Challenge (IOI22_prison)	C++17	65 / 100	14 ms	1116 KiB

prison

#include "prison.h"
#include "bits/stdc++.h"
using namespace std;

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<vvi> vvvi;
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()

std::vector<std::vector<int>> devise_strategy(int N)
{
  int d = 1;
  while (1 << (d + 1) <= N)
    ++d;
  vvi ans(2 * d + 2, vi(N + 1));

  vi bagSmaller = {-1, -2};

  int bag = 0;
  ans[0][0] = bag;
  for (int i = 1; i <= N; ++i)
    ans[0][i] = ((1 << d) & i) ? 2 * d + 1 : 2 * d;

  for (int j = d; j > 0; --j)
  {
    bag ^= 1;
    ans[2 * j][0] = ans[2 * j + 1][0] = bag;
    for (int i = 1; i <= N; ++i)
      if (i & (1 << j))
      {
        if (j > 1)
          ans[2 * j + 1][i] = 2 * (j - 1) + ((i >> (j - 1)) & 1);
        else
          ans[2 * j + 1][i] = bagSmaller[bag ^ (i & 1)];
        ans[2 * j][i] = bagSmaller[bag ^ 1];
      }
      else
      {
        ans[2 * j + 1][i] = bagSmaller[bag];
        if (j > 1)
          ans[2 * j][i] = 2 * (j - 1) + ((i >> (j - 1)) & 1);
        else
          ans[2 * j][i] = bagSmaller[bag ^ (i & 1)];
      }
  }

  for (int j = 2; j < sz(ans); ++j)
    swap(ans[j - 1], ans[j]);
  ans.pop_back();
  for (int j = 0; j < sz(ans); ++j)
    for (int i = 1; i < sz(ans[j]); ++i)
      if (ans[j][i] > 0)
        --ans[j][i];
  return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 55 / 90