Submission #1070398

#	Time	Username	Problem	Language	Result	Execution time	Memory
1070398		andrei_iorgulescu	Counting Mushrooms (IOI20_mushrooms)	C++14	92.62 / 100	6 ms	600 KiB

mushrooms

#include <bits/stdc++.h>
#include "mushrooms.h"
#warning That's not FB, that's my FB

using namespace std;

int count_mushrooms(int n)
{
    vector<int> A, B;
    A.push_back(0);
    if (n <= 227)
    {
        int ans = 1;
        for (int i = 1; i < n; i++)
            ans += 1 - use_machine({0,i});
        return ans;
    }
    int hh = use_machine({0,1}), hhh = use_machine({0,2});
    if (hh == 0)
        A.push_back(1);
    else
        B.push_back(1);
    if (hh == 1)
    {
        if (hhh == 0)
            A.push_back(2);
        else
            B.push_back(2);
    }
    int a = A.size(), b = B.size();
    ///caut cel mai bun max(a,b) la care sa ma opresc din spamat
    int best, omin = 1e9;
    for (int i = 5; i <= 1000 and 2 * i <= n; i++)
    {
        int cur = i - 1;
        int cate = n - 2 * i;
        int j = -1;
        while (cate > 0)
        {
            j++;
            cur++;
            cate -= (i + j / 2);
        }
        if (cur < omin)
        {
            omin = cur;
            best = i;
        }
    }
    best += 3;
    vector<int> unsolved;
    if (hh == 1)
    {
        for (int i = 3; i < n; i++)
            unsolved.push_back(i);
    }
    else
    {
        for (int i = 2; i < n; i++)
            unsolved.push_back(i);
    }
    reverse(unsolved.begin(),unsolved.end());
    while (max(a,b) < best)
    {
        if (a >= 2)
        {
            vector<int> mac = {unsolved[unsolved.size() - 1], A[0], unsolved[unsolved.size() - 2], A[1]};
            int xxx = use_machine(mac);
            if (xxx == 0)
            {
                A.push_back(unsolved.back());
                unsolved.pop_back();
                A.push_back(unsolved.back());
                unsolved.pop_back();
            }
            else if (xxx == 1)
            {
                B.push_back(unsolved.back());
                unsolved.pop_back();
                A.push_back(unsolved.back());
                unsolved.pop_back();
            }
            else if (xxx == 2)
            {
                A.push_back(unsolved.back());
                unsolved.pop_back();
                B.push_back(unsolved.back());
                unsolved.pop_back();
            }
            else
            {
                B.push_back(unsolved.back());
                unsolved.pop_back();
                B.push_back(unsolved.back());
                unsolved.pop_back();
            }
        }
        else
        {
            vector<int> mac = {unsolved[unsolved.size() - 1], B[0], unsolved[unsolved.size() - 2], B[1]};
            int xxx = use_machine(mac);
            if (xxx == 0)
            {
                B.push_back(unsolved.back());
                unsolved.pop_back();
                B.push_back(unsolved.back());
                unsolved.pop_back();
            }
            else if (xxx == 1)
            {
                A.push_back(unsolved.back());
                unsolved.pop_back();
                B.push_back(unsolved.back());
                unsolved.pop_back();
            }
            else if (xxx == 2)
            {
                B.push_back(unsolved.back());
                unsolved.pop_back();
                A.push_back(unsolved.back());
                unsolved.pop_back();
            }
            else
            {
                A.push_back(unsolved.back());
                unsolved.pop_back();
                A.push_back(unsolved.back());
                unsolved.pop_back();
            }
        }
        a = A.size();
        b = B.size();
    }
    int ans = A.size();
    while (!unsolved.empty())
    {
        int k = max(a,b);
        vector<int> cr;
        for (int i = 0; i < k; i++)
        {
            if (!unsolved.empty())
            {
                cr.push_back(unsolved.back());
                unsolved.pop_back();
            }
        }
        if (a >= b)
        {
            vector<int> tq;
            for (int i = 0; i < cr.size(); i++)
            {
                tq.push_back(cr[i]);
                tq.push_back(A[i]);
            }
            int xxx = use_machine(tq);
            if (xxx % 2 == 1)
                B.push_back(cr[0]), xxx--;
            else
                A.push_back(cr[0]), ans++;
            ans += (2 * ((int)cr.size() - 1) - xxx) / 2;
        }
        else
        {
            vector<int> tq;
            for (int i = 0; i < cr.size(); i++)
            {
                tq.push_back(cr[i]);
                tq.push_back(B[i]);
            }
            int xxx = use_machine(tq);
            if (xxx % 2 == 1)
                A.push_back(cr[0]), ans++, xxx--;
            else
                B.push_back(cr[0]);
            ans += xxx / 2;
        }
        a = A.size();
        b = B.size();
    }
    return ans;
}

/**
Aflu sa zicem doua A-uri, dau spamez AxAy ca unic determina x si y, candva ma opresc
Sa zicem ca am a A-uri si b B-uri
While (mai am nedescoperite)
{
k = max(a,b);
Bag x1Ax2A...xkA, astfel aflu cate din x sunt A-uri dar aflu si exact cum e x1, il bag in A-uri sau B-uri si dau a++ sau b++
}

Fara ultima optimizare era fix 2sqrt, asa idk, doamne ajuta
**/

Compilation message (stderr)

mushrooms.cpp:3:2: warning: #warning That's not FB, that's my FB [-Wcpp]
    3 | #warning That's not FB, that's my FB
      |  ^~~~~~~
mushrooms.cpp: In function 'int count_mushrooms(int)':
mushrooms.cpp:150:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  150 |             for (int i = 0; i < cr.size(); i++)
      |                             ~~^~~~~~~~~~~
mushrooms.cpp:165:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  165 |             for (int i = 0; i < cr.size(); i++)
      |                             ~~^~~~~~~~~~~
mushrooms.cpp:50:10: warning: 'best' may be used uninitialized in this function [-Wmaybe-uninitialized]
   50 |     best += 3;
      |     ~~~~~^~~~

• Subtask 1: 92.623 / 100