Submission #802169

#	Time	Username	Problem	Language	Result	Execution time	Memory
802169		lollipop	Counting Mushrooms (IOI20_mushrooms)	C++17	56.93 / 100	10 ms	612 KiB

mushrooms

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
#define ll long long
#define pb push_back
#define s second
#define f first
#define pf push_front
#define inf 100000000000000000
#define bitebi __builtin_popcountll
#define FOR( i , n ) for( int i = 0 ; i < n ; i ++ )
#define YES cout <<"YES\n"
#define NO cout << "NO\n"
#define debug cout << "Here Fine" << endl ;
#define pr pair < int , int >
#define fbo find_by_order // returns iterator
#define ook order_of_key // returns strictly less numbers than key
using namespace std ;
//#pragma GCC optimize("Ofast")
//#pragma GCC target("avx,avx2,fma")
using namespace __gnu_pbds;
using namespace __gnu_cxx;
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
const double Pi=acos(-1.0);
const double EPS=1E-8;
const int mod =  1000000007 ;
const int mod1 = 998244353 ;
const int NN = 2e5 + 10 ;
//mt19937 R(time(0));
int myrandom (int i) { return std::rand()%i;}
map < int , int > ma , ma1 ;

#include "mushrooms.h"

// int use_machine(std::vector<int> x){

// }


int count_mushrooms(int n){
    std::srand ( unsigned ( std::time(0) ) );
    vector < int > a , b ; 
    a.pb( 0 ) ;
    int st ; 
    vector < int > vv ;
    for( int j = 1 ; j < n ; j ++ ) vv.pb( j ) ;
    random_shuffle( vv.begin() , vv.end() , myrandom) ;
   // random_shuffle( vv.begin() , vv.end() ) ;
    int vs = vv.size() ;
    for( int k = 0 ; k < min( vs , 200 ) ; k ++ ){
      vector < int > v ;
      int i = vv[ k ] ;
      v.pb( 0 ) ; v.pb( i );
      int x = use_machine( v ) ;
      if( x == 0 ) a.pb( i ) ;
      else b.pb( i ) ;
      if( a.size() >= 100 || b.size() >= 100 ){
        st = k + 1 ; break ;
      }
    }
    if( a.size() + b.size() == n ) return a.size() ;
    int tt = 0 ;
    if( a.size() < 100 ){
      tt = 1 ;
      swap( a , b ) ;
    }
    for( int j = st ; j < vv.size() ; j ++ ){
      int lf = vv.size() - j ; 
      int jj = j ; 
      vector < int > v ;
      int nw = 0 , cc = 0 ;
      if( lf >= 100 ){
        FOR( i , 100 ){
          v.pb( a[ i ] ) ;
          nw ++ ;
           v.pb( vv[jj] ) ; jj ++ ;
        }
      } 
      else{
        FOR( i , lf ){
          v.pb( a[ i ] ) ;
          nw ++ ;
          v.pb( vv[jj] ) ; jj ++ ;
        } 
      }
      int x = use_machine( v ) ;
      while( x > 0 ){
         b.pb( -1 ) ;
         cc ++ ;
         x -= 2 ;
      }
      cc = nw - cc ; 
      while( cc -- ) a.pb( -1 ) ;
      j = jj - 1 ;
    }



    if( tt == 0 ) return a.size() ;
    else return n - a.size() ;

}

//int use_machine(std::vector<int> x)

Compilation message (stderr)

mushrooms.cpp: In function 'int count_mushrooms(int)':
mushrooms.cpp:62:29: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   62 |     if( a.size() + b.size() == n ) return a.size() ;
      |         ~~~~~~~~~~~~~~~~~~~~^~~~
mushrooms.cpp:68:25: 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 = st ; j < vv.size() ; j ++ ){
      |                       ~~^~~~~~~~~~~
mushrooms.cpp:68:23: warning: 'st' may be used uninitialized in this function [-Wmaybe-uninitialized]
   68 |     for( int j = st ; j < vv.size() ; j ++ ){
      |                       ^

• Subtask 1: 56.927 / 100