Submission #956850

# Submission time Handle Problem Language Result Execution time Memory
956850 2024-04-02T14:47:16 Z Numberz Counting Mushrooms (IOI20_mushrooms) C++14
100 / 100
5 ms 876 KB
#include "mushrooms.h"
#include <bits/stdc++.h>
using namespace std;

//a contains the a and b, but easy to swap
vector<int> a[2], ve;
//res = answer, 
int res, x, c, k, r;

void update() {
  if (a[0].size() < a[1].size()) {
    res = r - res;
    swap(a[0], a[1]);
    c ^= 1;
  }
}

int count_mushrooms(int n) {
  //if n is small, we dont need to go through all this trouble, just check the all directly
  if (n <= 227) {
    for (int i = 1; i < n; i++) {
      res += 1 - use_machine({0, i});
    }
    return res + 1;
  }

  a[0] = {0};
  //clever way to not FALLUNTERSCHEID them
  for (int i = 1; i < 3; i++) {
    int x = use_machine({0, i});
    a[x].push_back(i);
  }
  update();
  //get at least 5 items
  x = use_machine({3, a[0][0], 4, a[0][1]});
  a[x&1].push_back(3);
  a[x/2&1].push_back(4);
  update();


  //in the first phase we collect as much explicit using this nice method
  //using 2 queries, we can determine 5 items
  //we find first explicit, then we know if the others are the same or dif
  //if same-> we know what, else we know they are different
  //in the last case we have limited number of possiblities, so just check all of them
  //with this nice trick
  for (int i = 5; max(a[0].size(), a[1].size()) < 100;) {
    x = use_machine({i, a[0][0], i+1, a[0][1], i+2, a[0][2]});
    a[x&1].push_back(i);
    if (!(x/2 % 2)) {
      a[x/4].push_back(i+1);
      a[x/4].push_back(i+2);
      i+=3;
    } else if (a[1].size() < 2) {
      x = use_machine({a[0][0], i+1});
      a[x].push_back(i+1);
      a[x^1].push_back(i+2);
      i+=3;
    } else {
      x = use_machine({i+4, a[0][0], i+3, a[0][1], i+2, a[0][2], a[1][0], i+1, a[1][1]})-1;
      a[x&1].push_back(i+4);
      a[x/2&1].push_back(i+3);
      a[x/4].push_back(i+2);
      a[x/4^1].push_back(i+1);
      i += 5;
    }
  }
  update();
  //now phase 2
  res = a[1].size();
  for (int i = a[0].size() + a[1].size(); i < n; i = r) {
    ve.clear();//(int)
    r = min(i+(int)a[0].size(), n);
    for (int j = i; j < r; j++) {
      ve.push_back(j);
      ve.push_back(a[0][j-i]);
    }
    x = use_machine(ve);
    res += (x+1)/2;
    a[x&1].push_back(i);
    update();
  }

  return (c ? res : n - res);
  
}
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 596 KB Output is correct
3 Correct 0 ms 344 KB Output is correct
4 Correct 0 ms 344 KB Output is correct
5 Correct 1 ms 344 KB Output is correct
6 Correct 1 ms 448 KB Output is correct
7 Correct 4 ms 708 KB Output is correct
8 Correct 4 ms 460 KB Output is correct
9 Correct 4 ms 460 KB Output is correct
10 Correct 5 ms 456 KB Output is correct
11 Correct 5 ms 456 KB Output is correct
12 Correct 5 ms 456 KB Output is correct
13 Correct 4 ms 460 KB Output is correct
14 Correct 2 ms 460 KB Output is correct
15 Correct 4 ms 460 KB Output is correct
16 Correct 5 ms 616 KB Output is correct
17 Correct 2 ms 460 KB Output is correct
18 Correct 5 ms 468 KB Output is correct
19 Correct 4 ms 464 KB Output is correct
20 Correct 4 ms 460 KB Output is correct
21 Correct 4 ms 460 KB Output is correct
22 Correct 4 ms 456 KB Output is correct
23 Correct 4 ms 460 KB Output is correct
24 Correct 3 ms 460 KB Output is correct
25 Correct 5 ms 712 KB Output is correct
26 Correct 4 ms 616 KB Output is correct
27 Correct 5 ms 456 KB Output is correct
28 Correct 4 ms 456 KB Output is correct
29 Correct 4 ms 460 KB Output is correct
30 Correct 5 ms 452 KB Output is correct
31 Correct 4 ms 460 KB Output is correct
32 Correct 4 ms 460 KB Output is correct
33 Correct 4 ms 652 KB Output is correct
34 Correct 4 ms 460 KB Output is correct
35 Correct 5 ms 460 KB Output is correct
36 Correct 4 ms 464 KB Output is correct
37 Correct 4 ms 712 KB Output is correct
38 Correct 4 ms 712 KB Output is correct
39 Correct 4 ms 460 KB Output is correct
40 Correct 4 ms 460 KB Output is correct
41 Correct 4 ms 460 KB Output is correct
42 Correct 4 ms 460 KB Output is correct
43 Correct 5 ms 460 KB Output is correct
44 Correct 4 ms 704 KB Output is correct
45 Correct 5 ms 456 KB Output is correct
46 Correct 4 ms 456 KB Output is correct
47 Correct 4 ms 704 KB Output is correct
48 Correct 4 ms 876 KB Output is correct
49 Correct 4 ms 708 KB Output is correct
50 Correct 4 ms 456 KB Output is correct
51 Correct 5 ms 708 KB Output is correct
52 Correct 4 ms 712 KB Output is correct
53 Correct 4 ms 460 KB Output is correct
54 Correct 4 ms 460 KB Output is correct
55 Correct 4 ms 456 KB Output is correct
56 Correct 4 ms 456 KB Output is correct
57 Correct 4 ms 456 KB Output is correct
58 Correct 5 ms 712 KB Output is correct
59 Correct 5 ms 460 KB Output is correct
60 Correct 5 ms 712 KB Output is correct
61 Correct 4 ms 460 KB Output is correct
62 Correct 0 ms 344 KB Output is correct
63 Correct 1 ms 344 KB Output is correct
64 Correct 0 ms 344 KB Output is correct
65 Correct 0 ms 344 KB Output is correct
66 Correct 0 ms 432 KB Output is correct
67 Correct 0 ms 344 KB Output is correct
68 Correct 0 ms 344 KB Output is correct
69 Correct 0 ms 344 KB Output is correct
70 Correct 0 ms 344 KB Output is correct
71 Correct 1 ms 344 KB Output is correct
72 Correct 1 ms 344 KB Output is correct
73 Correct 0 ms 348 KB Output is correct
74 Correct 0 ms 352 KB Output is correct
75 Correct 0 ms 344 KB Output is correct
76 Correct 1 ms 344 KB Output is correct
77 Correct 0 ms 348 KB Output is correct
78 Correct 0 ms 348 KB Output is correct
79 Correct 0 ms 348 KB Output is correct
80 Correct 0 ms 348 KB Output is correct
81 Correct 0 ms 348 KB Output is correct
82 Correct 0 ms 344 KB Output is correct
83 Correct 0 ms 348 KB Output is correct
84 Correct 0 ms 348 KB Output is correct
85 Correct 0 ms 348 KB Output is correct
86 Correct 0 ms 348 KB Output is correct
87 Correct 0 ms 348 KB Output is correct
88 Correct 1 ms 348 KB Output is correct
89 Correct 0 ms 344 KB Output is correct
90 Correct 1 ms 344 KB Output is correct
91 Correct 0 ms 500 KB Output is correct