Submission #1052151

#	Time	Username	Problem	Language	Result	Execution time	Memory
1052151		Huseyn123	Counting Mushrooms (IOI20_mushrooms)	C++17	25 / 100	64 ms	1144 KiB

mushrooms

#include "mushrooms.h"
#include <bits/stdc++.h> 
using namespace std; 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int count_mushrooms(int n) {
	vector<int> c;
	for(int i=1;i<n;i++){
		c.push_back(i);
	}
	shuffle(c.begin(),c.end(),rng);
	vector<int> v0,v1;
	v0.push_back(0);
	int cnt=0;
	int i=0;
	while(i<n-1){
		if((v0.size()<2 && v1.size()<2) || i==n-2){
			int h=use_machine({c[i],0});
			if(h==0){
				v0.push_back(c[i]);
			}
			else{
				v1.push_back(c[i]);
			}
			cnt=i+1;
			i++;
		}
		else{
			if(v0.size()>=2){
				int h=use_machine({v0[0],c[i],v0[1],c[i+1]});
				if(h==0){
					v0.push_back(c[i]); 
					v0.push_back(c[i+1]);
				}
				else if(h==1){
					v1.push_back(c[i+1]);
					v0.push_back(c[i]);
				}
				else if(h==2){
					v1.push_back(c[i]);
					v0.push_back(c[i+1]);
				}
				else{
					v1.push_back(c[i]); 
					v1.push_back(c[i+1]);
				}
			}
			else{
				int h=use_machine({v1[0],c[i],v1[1],c[i+1]});
				if(h==0){
					v1.push_back(c[i]); 
					v1.push_back(c[i+1]);
				}
				else if(h==1){
					v0.push_back(c[i+1]);
					v1.push_back(c[i]);
				}
				else if(h==2){
					v0.push_back(c[i]);
					v1.push_back(c[i+1]);
				}
				else{
					v0.push_back(c[i]); 
					v0.push_back(c[i+1]);
				}
			}
			cnt=i+2;
			i+=2;
		}
		int mx=max((int)v0.size(),(int)v1.size());
		if(mx>1 && cnt/2+(n-cnt-1)/(mx-1)<280){
			break;
		}
	}
	int res=(int)v0.size();
	vector<int> v=v0;
	int tp=0; 
	if((int)v1.size()>(int)v0.size()){
		tp=1;
		v=v1;
	}
	vector<int> d;
	for(int i=cnt;i<n-1;i++){
		d.push_back(v[(int)d.size()/2]);
		d.push_back(c[i]);
		if((int)d.size()==2*v.size()-2){
			d.push_back(v.back());
			int h=use_machine(d);
			int sz=(int)d.size();
			d.clear();
			if(tp){
				res+=h/2;
			}
			else{
				res+=sz/2-h/2;
			}
		}
	}
	if((int)d.size()>0){
		d.push_back(v.back());
		int h=use_machine(d);
		int sz=(int)d.size();
		d.clear();
		if(tp){
			res+=h/2;
		}
		else{
			res+=sz/2-h/2;
		}
	}
	return res; 
}

Compilation message (stderr)

mushrooms.cpp: In function 'int count_mushrooms(int)':
mushrooms.cpp:85:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   85 |   if((int)d.size()==2*v.size()-2){
      |      ~~~~~~~~~~~~~^~~~~~~~~~~~~~

• Subtask 1: 25 / 100