Submission #952709

#	Time	Username	Problem	Language	Result	Execution time	Memory
952709		kilkuwu	Library (JOI18_library)	C++11	0 / 100	16 ms	696 KiB

library

#include <bits/stdc++.h>


#ifndef LOCAL
#include "library.h"
#else
#include <vector>
int Query(const std::vector<int>& M);
void Answer(const std::vector<int>& res);
#endif

void Solve(int N) {
  std::vector<int> dp(N + 1, -1);

  auto get_pref = [&](int x) {
    if (dp[x] != -1) return dp[x];
    std::vector<int> a(N);
    for (int i = 0; i < x; i++) {
      a[i] = 1;
    }
    return dp[x] = Query(a);
  };

  auto get_pref_more = [&](int x, int y) {
    std::vector<int> a(N);
    a[y - 1] = 1;
    for (int i = 0; i < x; i++) {
      a[i] = 1;
    }
    return Query(a);
  };

  std::vector<std::vector<int>> adj(N + 1);

  dp[1] = 1;
  for (int i = 2; i <= N; i++) {
    if (get_pref(i) - get_pref(i - 1) == 1) {
      continue;
    }

    if (get_pref(i) - get_pref(i - 1) == 0) {
      int lb = 1, rb = i - 1; 
      while (lb < rb) {
        int mid = (lb + rb) / 2;
        int bef = get_pref(mid);
        int aft = get_pref_more(mid, i);
        if (aft - bef == 0) {
          rb = mid;
        } else {
          lb = mid + 1;
        }
      }
      adj[rb].push_back(i);
      adj[i].push_back(rb);
      continue;
    }

    assert(get_pref(i) - get_pref(i - 1) == -1);

    int lb = 1, rb = i - 1;
    while (lb < rb) {
      int mid = (lb + rb) / 2;
      int bef = get_pref(mid);
      int aft = get_pref_more(mid, i);

      if (aft - bef == -1) { // now we can be sure
        rb = mid;
      } else {
        lb = mid + 1;
      }
    }

    int z = rb;

    adj[z].push_back(i);
    adj[i].push_back(z);

    lb = 1, rb = z - 1; // z - 1 
    while (lb < rb) {
      int mid = (lb + rb) / 2;
      int bef = get_pref(mid);
      int aft = get_pref_more(mid, i);

      if (aft - bef == 0) {
        rb = mid;
      } else {
        lb = mid + 1;
      }
    }

    adj[rb].push_back(i);
    adj[i].push_back(rb);
  }

  std::vector<int> res;

  std::function<void(int, int)> dfs = [&](int u, int p) {
    res.push_back(u);
    for (int v : adj[u]) {
      if (v == p) continue;
      dfs(v, u);
    }
  };


  for (int i = 1; i <= N; i++) {
    if ((int) adj[i].size() == 1) {
      dfs(i, i);
      break;
    }
  }

  assert(res.size() == N);
  Answer(res);
}

Compilation message (stderr)

In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from library.cpp:1:
library.cpp: In function 'void Solve(int)':
library.cpp:113:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  113 |   assert(res.size() == N);
      |          ~~~~~~~~~~~^~~~

• Subtask 1: 0 / 19
• Subtask 2: 0 / 81