Submission #642060

#	Time	Username	Problem	Language	Result	Execution time	Memory
642060		valerikk	Library (JOI18_library)	C++17	100 / 100	306 ms	336 KiB

library

#include <cstdio>
#include <vector>
#include <cassert>
#include <iostream>

#include "library.h"

using namespace std;

void Solve(int n) {
  if (n == 1) {
    Answer({1});
    return;
  }

  vector<int> ends;
  for (int i = 0; i < n; ++i) {
    vector<int> a(n, 1);
    a[i] = 0;
    if (Query(a) == 1) {
      ends.push_back(i);
    }
  }

  assert(ends.size() == 2);
  
  vector<int> p(n);
  p[0] = ends[0];
  p[n - 1] = ends[1];

  vector<bool> used(n, false);
  used[p[0]] = true;
  used[p[n - 1]] = true;

  // cout << p[0] << " " << p[n - 1] << "\n";

  int l = 0, r = n - 1;
  while (l + 1 < r) {
    vector<int> a;
    for (int i = 0; i < n; ++i) {
      if (!used[i]) a.push_back(i);
    }

    if (l + 1 == r) {
      p[l + 1] = a[0];
      break;
    }

    int l_id = 0, r_id = 0;

    int sz = a.size();
    for (int t = 0; (1 << t) < sz; ++t) {
      vector<int> v(n, 0);
      for (int i = 0; i < sz; ++i) {
        if ((i >> t) & 1) v[a[i]] = 1;
      }

      int ans00 = Query(v);

      v[p[l]] = 1;
      int ans10 = Query(v);
      v[p[l]] = 0;

      v[p[r]] = 1;
      int ans01 = Query(v);
      v[p[r]] = 0;

      v[p[l]] = 1;
      v[p[r]] = 1;
      int ans11 = Query(v);
      v[p[l]] = 0;
      v[p[r]] = 0;

      if (ans00 == ans11) {
        l_id += 1 << t;
        r_id += 1 << t;
        continue;
      }

      if (ans00 + 2 == ans11) {
        continue;
      }

      assert(ans10 != ans01);

      if (ans10 < ans01) {
        l_id += 1 << t;
      } else {
        r_id += 1 << t;
      }
    } 

    ++l;
    --r;
    p[l] = a[l_id];
    p[r] = a[r_id];
    used[p[l]] = true;
    used[p[r]] = true;
  }

  for (int i = 0; i < n; ++i) {
    ++p[i];
  }
  Answer(p);
}

• Subtask 1: 19 / 19
• Subtask 2: 81 / 81