oj.uz

Submission #217163

# Submission time Handle Problem Language Result Execution time Memory
217163 2020-03-29T07:10:49 Z rama_pang Chameleon's Love (JOI20_chameleon) C++14
100 / 100
 67 ms 504 KB 
#include "chameleon.h"
#include <bits/stdc++.h>
using namespace std;

vector<pair<int, int>> edges; // edges(a, b) if Query({a, b}) = 1

void FindEdges(vector<int> candidates, int n) { // find edges from one of vertices in candidates to i
  int lo = 0, hi = (int) candidates.size() - 1;

  while (lo < hi) {
    int mid = (lo + hi) / 2;
    vector<int> q(begin(candidates), begin(candidates) + mid + 1);
    q.emplace_back(n);
    if (Query(q) < q.size()) {
      hi = mid;
    } else {
      lo = mid + 1;
    }
  }

  edges.emplace_back(candidates[hi], n); // set(candidates[1...hi] + n) has an edge while set(candidates[1...hi-1] + n) doesn't, means there is an edge between candidates[hi] and n

  vector<int> new_candidates(begin(candidates) + hi + 1, end(candidates));  
  vector<int> q(new_candidates); 
  q.emplace_back(n);

  if (Query(q) < q.size()) { // there is an edge between new_candidates and n
    return FindEdges(new_candidates, n);
  }
}

void Solve(int N) {
  vector<vector<int>> ind(4); // independent sets

  for (int i = 1; i <= 2 * N; i++) {
    vector<bool> is_independent(4, false); // is ind[j] independent after adding i?
    
    for (int j = 0; j < 4; j++) {
      vector<int> q(ind[j]);
      q.emplace_back(i);
      if (Query(q) < q.size()) { // there is an edge between ind[j] and i
        FindEdges(ind[j], i);
      } else { 
        is_independent[j] = true; // adding i to ind[j] still maintain its independency
      }
    }

    for (int j = 0; j < 4; j++) {
      if (is_independent[j]) { // adding i to ind[j] still maintain its independency, so we can put i in ind[j]
        ind[j].emplace_back(i);
        break;
      }
    }
  }

  vector<vector<int>> adj(2 * N + 1);
  vector<bool> determined(2 * N + 1, false); // determined[i] means i has already been answered

  for (auto &e : edges) {
    int a = e.first, b = e.second;
    adj[a].emplace_back(b);
    adj[b].emplace_back(a);
  }

  auto IsSpecial = [&](int a, int b) { // determine if a and b has the same color
    vector<int> all_except_a_and_b;
    for (int i = 1; i <= 2 * N; i++) {
      if (i == a || i == b) continue;
      all_except_a_and_b.emplace_back(i);
    }
    return Query(all_except_a_and_b) < N; // If query returns N, then a and b is not the same color
  };

  for (int i = 1; i <= 2 * N; i++) {
    if (determined[i]) continue;
    for (auto &j : adj[i]) {
      if (determined[j]) continue;
      if (IsSpecial(i, j)) {
        determined[i] = true;
        determined[j] = true;
        Answer(i, j);
        break;
      }
    }
  }
}

Compilation message

chameleon.cpp: In function 'void FindEdges(std::vector<int>, int)':
chameleon.cpp:14:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if (Query(q) < q.size()) {
         ~~~~~~~~~^~~~~~~~~~
chameleon.cpp:27:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (Query(q) < q.size()) { // there is an edge between new_candidates and n
       ~~~~~~~~~^~~~~~~~~~
chameleon.cpp: In function 'void Solve(int)':
chameleon.cpp:41:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       if (Query(q) < q.size()) { // there is an edge between ind[j] and i
           ~~~~~~~~~^~~~~~~~~~

Subtask #1
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 39 ms 384 KB Output is correct
4 Correct 39 ms 504 KB Output is correct
5 Correct 39 ms 384 KB Output is correct
6 Correct 38 ms 384 KB Output is correct
7 Correct 39 ms 384 KB Output is correct
8 Correct 38 ms 384 KB Output is correct
9 Correct 40 ms 384 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 360 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 360 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 5 ms 384 KB Output is correct
12 Correct 5 ms 384 KB Output is correct
13 Correct 6 ms 384 KB Output is correct
14 Correct 6 ms 384 KB Output is correct
15 Correct 6 ms 384 KB Output is correct
16 Correct 5 ms 384 KB Output is correct
17 Correct 7 ms 384 KB Output is correct
18 Correct 6 ms 384 KB Output is correct

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 64 ms 428 KB Output is correct
4 Correct 63 ms 384 KB Output is correct
5 Correct 65 ms 384 KB Output is correct
6 Correct 61 ms 384 KB Output is correct
7 Correct 67 ms 384 KB Output is correct
8 Correct 61 ms 384 KB Output is correct
9 Correct 61 ms 384 KB Output is correct

Subtask #5
36.0 / 36.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 39 ms 384 KB Output is correct
4 Correct 39 ms 504 KB Output is correct
5 Correct 39 ms 384 KB Output is correct
6 Correct 38 ms 384 KB Output is correct
7 Correct 39 ms 384 KB Output is correct
8 Correct 38 ms 384 KB Output is correct
9 Correct 40 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 5 ms 360 KB Output is correct
12 Correct 4 ms 384 KB Output is correct
13 Correct 4 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 4 ms 384 KB Output is correct
16 Correct 4 ms 384 KB Output is correct
17 Correct 5 ms 384 KB Output is correct
18 Correct 5 ms 384 KB Output is correct
19 Correct 5 ms 384 KB Output is correct
20 Correct 5 ms 384 KB Output is correct
21 Correct 5 ms 384 KB Output is correct
22 Correct 6 ms 384 KB Output is correct
23 Correct 6 ms 384 KB Output is correct
24 Correct 6 ms 384 KB Output is correct
25 Correct 5 ms 384 KB Output is correct
26 Correct 7 ms 384 KB Output is correct
27 Correct 6 ms 384 KB Output is correct
28 Correct 4 ms 384 KB Output is correct
29 Correct 4 ms 384 KB Output is correct
30 Correct 64 ms 428 KB Output is correct
31 Correct 63 ms 384 KB Output is correct
32 Correct 65 ms 384 KB Output is correct
33 Correct 61 ms 384 KB Output is correct
34 Correct 67 ms 384 KB Output is correct
35 Correct 61 ms 384 KB Output is correct
36 Correct 61 ms 384 KB Output is correct
37 Correct 57 ms 384 KB Output is correct
38 Correct 39 ms 384 KB Output is correct
39 Correct 66 ms 384 KB Output is correct
40 Correct 64 ms 384 KB Output is correct
41 Correct 57 ms 384 KB Output is correct
42 Correct 40 ms 384 KB Output is correct
43 Correct 61 ms 384 KB Output is correct
44 Correct 58 ms 424 KB Output is correct
45 Correct 58 ms 384 KB Output is correct