Submission #1080645

#	Time	Username	Problem	Language	Result	Execution time	Memory
1080645		Faisal_Saqib	Counting Mushrooms (IOI20_mushrooms)	C++17	87.94 / 100	9 ms	856 KiB

mushrooms

#include "mushrooms.h"
#include <bits/stdc++.h>
using namespace std;
mt19937 RNG(chrono::steady_clock::now().time_since_epoch().count());  
#define SHUFFLE(v) shuffle(begin(v),end(v), RNG); 
int count_mushrooms(int n) {
	std::vector<int> ind[2];
	ind[0].push_back(0);
	int sq=33;
	int rem_i=1;
	vector<int> order_fake;
	for(int j=1;j<n;j++)
		order_fake.push_back(j);
	SHUFFLE(order_fake);
	vector<int> order={0};
	for(auto j:order_fake)
		order.push_back(j);
	for(int i=1;i<n and max(ind[0].size(),ind[1].size())<sq;i++,rem_i++)
	{
		if(ind[0].size()>=2 and (i+1)<n)
		{
			int i0=order[i],i1=order[i+1];
			vector<int> query={ind[0][0],i0,ind[0][1],i1};
			int x=use_machine(query);
			if((x&1)==1)
			{
				ind[1].push_back(i1);
			}
			else
			{
				ind[0].push_back(i1);
			}
			if((x&2)==2)
			{
				ind[1].push_back(i0);
			}
			else
			{
				ind[0].push_back(i0);
			}
			i++;
			rem_i++;
		}
		else if(ind[1].size()>=2 and (i+1)<n)
		{
			int i0=order[i],i1=order[i+1];
			vector<int> query={ind[1][0],i0,ind[1][1],i1};
			int x=3-use_machine(query);
			if((x&1)==1)
			{
				ind[1].push_back(i1);
			}
			else
			{
				ind[0].push_back(i1);
			}
			if((x&2)==2)
			{
				ind[1].push_back(i0);
			}
			else
			{
				ind[0].push_back(i0);
			}
			i++;
			rem_i++;
		}
		else
		{			
			int i0=order[i];
			ind[0].push_back(i0);
			int x=use_machine(ind[0]);
			ind[0].pop_back();
			if(x==0)
			{
				ind[0].push_back(i0);
			}
			else
			{
				ind[1].push_back(i0);
			}
		}
	}
	int ans=ind[0].size();
	for(int i=rem_i;i<n;)
	{
		if(ind[0].size()>=ind[1].size())
		{
			vector<int> query;
			int rem=min(n-i,(int)ind[0].size());
			for(int j=0;j<rem;j++)
			{
				query.push_back(ind[0][j]);
				query.push_back(order[i+j]);
			}
			int x=use_machine(query);
			int ones=(x+1)/2;
			int zeros=rem-ones;
			ans+=zeros;
			if(zeros==0)
			{
				for(int j=1;j<query.size();j+=2)
				{
					ind[1].push_back(query[j]);
				}
			}
			else if(zeros==rem)
			{
				for(int j=1;j<query.size();j+=2)
				{
					ind[0].push_back(query[j]);
				}
			}
			else
			{
				if(x%2==0)
				{
					ind[0].push_back(order[i+rem-1]);
				}
				else
				{
					ind[1].push_back(order[i+rem-1]);
				}
			}
			i+=rem;
		}
		else
		{
			vector<int> query;
			int rem=min(n-i,(int)ind[1].size());
			for(int j=0;j<rem;j++)
			{
				query.push_back(ind[1][j]);
				query.push_back(order[i+j]);
			}
			int x=use_machine(query);
			int zeros=(x+1)/2;
			ans+=zeros;
			if(zeros==0)
			{
				for(int j=1;j<query.size();j+=2)
				{
					ind[1].push_back(query[j]);
				}
			}
			else if(zeros==rem)
			{
				for(int j=1;j<query.size();j+=2)
				{
					ind[0].push_back(query[j]);
				}
			}
			else
			{
				if(x%2==1)
				{
					ind[0].push_back(order[i+rem-1]);
				}
				else
				{
					ind[1].push_back(order[i+rem-1]);
				}
			}
			i+=rem;
		}
	}
	return ans;
}

Compilation message (stderr)

mushrooms.cpp: In function 'int count_mushrooms(int)':
mushrooms.cpp:18:54: warning: comparison of integer expressions of different signedness: 'const long unsigned int' and 'int' [-Wsign-compare]
   18 |  for(int i=1;i<n and max(ind[0].size(),ind[1].size())<sq;i++,rem_i++)
      |                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
mushrooms.cpp:102:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  102 |     for(int j=1;j<query.size();j+=2)
      |                 ~^~~~~~~~~~~~~
mushrooms.cpp:109:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  109 |     for(int j=1;j<query.size();j+=2)
      |                 ~^~~~~~~~~~~~~
mushrooms.cpp:141:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  141 |     for(int j=1;j<query.size();j+=2)
      |                 ~^~~~~~~~~~~~~
mushrooms.cpp:148:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  148 |     for(int j=1;j<query.size();j+=2)
      |                 ~^~~~~~~~~~~~~

• Subtask 1: 87.9377 / 100