Submission #1037099

#	Time	Username	Problem	Language	Result	Execution time	Memory
1037099		Raimond	Counting Mushrooms (IOI20_mushrooms)	C++17	61.58 / 100	7 ms	600 KiB

mushrooms

#include "mushrooms.h"
#include <bits/stdc++.h>
using namespace std;
 
#define N '\n';
#define VI <vector <int>>
#define VVI <vector <vector <int>>>  
 
int count_mushrooms(int n){
    int cnt = 1;    
    
    if(n <= 226){
        for(int i = 1; i < n; i++){
            cnt += 1 - use_machine({0, i});
        }
        return cnt;
    }
 
    vector <int> As = {0};
    vector <int> Bs;
    
    int mn = 10000, ans;
    for(int i = 1; i < 500; i++){
        if(2*i + ((n - (2*i)) / i) < mn){
            mn = 2*i + ((n - (2*i)) / i);
            ans = i;
        }
    }
 
    int unt = ans*2;
    // 188 - 1 = 187
    for(int i = 1; i < unt; i++){
        bool q = use_machine({0,i});
        if(q)
            Bs.push_back(i);
        else
            As.push_back(i);
    }
    cnt += As.size()-1;
    
    int i = unt;
    // n - 188 / 94
    for(; i < n;){
        if(As.size() >= Bs.size()){
            vector<int> search;
            vector <int> Is;
            int j = 0;
            for(; j < As.size() && i < n; j++ ){
                search.push_back(i);
                Is.push_back(i);
                search.push_back(As[j]);
                i++;
            }
            int q = use_machine(search);
            cnt +=  (search.size()/2) - ((q/2) +(q % 2));
            if(q/2 + q % 2 == 0){
                for(int ii = 0; ii < Is.size(); ii++){
                    As.push_back(Is[ii]);
                }
            }
            if(q % 2 != 0){
                Bs.push_back(Is[0]);
            }
        }
        else{
            vector<int> search;
            vector <int> Is;
            for(int j = 0; j < Bs.size() && i < n; j++){
                search.push_back(i);
                Is.push_back(i);
                search.push_back(Bs[j]);
                i++;
            }
 
            int q = use_machine(search);
            cnt +=  q/2 + q % 2;
            if(q/2 + q % 2 == 0 ){
                for(int ii = 0; ii < Is.size(); ii++){
                    Bs.push_back(Is[ii]);
                }
            }
            if(q % 2 != 0){
                As.push_back(Is[0]);
            }  
        }
    }
    // B A B A B A
    // B A A A B A B A
    return cnt;
}

Compilation message (stderr)

mushrooms.cpp: In function 'int count_mushrooms(int)':
mushrooms.cpp:48:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |             for(; j < As.size() && i < n; j++ ){
      |                   ~~^~~~~~~~~~~
mushrooms.cpp:57:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |                 for(int ii = 0; ii < Is.size(); ii++){
      |                                 ~~~^~~~~~~~~~~
mushrooms.cpp:68:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |             for(int j = 0; j < Bs.size() && i < n; j++){
      |                            ~~^~~~~~~~~~~
mushrooms.cpp:78:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   78 |                 for(int ii = 0; ii < Is.size(); ii++){
      |                                 ~~~^~~~~~~~~~~
mushrooms.cpp:30:9: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   30 |     int unt = ans*2;
      |         ^~~

• Subtask 1: 61.5804 / 100