Submission #871175

#	Time	Username	Problem	Language	Result	Execution time	Memory
871175		Lib	Rarest Insects (IOI22_insects)	C++17	Compilation error	0 ms	0 KiB

insects

#include <bits/stdc++.h>
#include "insects.h"
//#include "stub.cpp"
using namespace std;
 
deque <int> PrevIndex;
int InMachine[2003];
int Permutation[2003];
//saving the answer of each iteration so that we won't accidentially binsearch something we've already calculated
int ok[2003];
int n;
int TypeCount=0;
int CurrentInMachine=0;
 
int PossibleMincount(int cnt){
	PrevIndex.clear();
	if(ok[cnt]){
		return 1;
	}
	//Pushing insects inside the machine, keeping track of the ones being putted inside for this iteration of binary searching
	for(int i=0;i<N;i++){
		if(!InMachine[Permutation[i]]){
			InMachine[Permutation[i]]=1;
			move_inside(Permutation[i]);
			PrevIndex.push_back(Permutation[i]);
			if(press_button()>cnt){
				move_outside(Permutation[i]);
				InMachine[Permutation[i]]=0;
				PrevIndex.pop_back();
			}
		}
	}
	CurrentInMachine=0;
	for(int i=0;i<N;i++){
		CurrentInMachine+=InMachine[Permutation[i]];
	}
	if(CurrentInMachine!=cnt*TypeCount){
		//There clearly exist a type of insect with cardinality less than cnt, so the answer is less than cnt. Removing insects from last iteration.
		while(!PrevIndex.empty()){
			InMachine[PrevIndex.front()]=0;
			move_outside(PrevIndex.front());
			PrevIndex.pop_front();
		}	
		PrevIndex.clear();
		return 0;
	}else if(CurrentInMachine==cnt*TypeCount){
		//As every type of insects has at least cnt insects, the answer is at least cnt. Just return true
		PrevIndex.clear();
		for(int i=1;i<=cnt;i++){
			ok[i]=1;
		}
		return 1;
	}
}
 
int min_cardinality(int N){
	//Create a random permutation to fuck with shitty tests and achieve better query efficiency
	for(int i=0;i<N;i++){
		Permutation[i]=i;
	}
	srand(time(NULL));
	int Tempval;
	for(int i=N-1;i>0;i--){
		Tempval=rand()%i;
		swap(Permutation[i],Permutation[Tempval]);
	}
	//Remember to initialize as this is multitest
	for(int i=0;i<N;i++){
    InMachine[Permutation[i]]=0;
    ok[i+1]=0;
    }
    PrevIndex.clear();
	int l,r,mid;
	//Phase 1: Determining the amount of different types of insects
	for(int i=0;i<n;i++){
		move_inside(Permutation[i]);
		InMachine[Permutation[i]]=1;
		PrevIndex.push_back(Permutation[i]);
		if(press_button()>1){
			move_outside(Permutation[i]);
			InMachine[Permutation[i]]=0;
			PrevIndex.pop_back();
		}
	}
	TypeCount=PrevIndex.size();
	r=(N/TypeCount);
	l=1;
	//Phase 2: Binary search for the answer
	while(r-l>1){
		mid=(l+r)/2;
		if(PossibleMincount(mid)){
			l=mid;
		}else{
			r=mid-1;
		}
	}
	if(PossibleMincount(r)){
		return r;
	}else{
		return l;
	}
}

Compilation message (stderr)

insects.cpp: In function 'int PossibleMincount(int)':
insects.cpp:21:16: error: 'N' was not declared in this scope
   21 |  for(int i=0;i<N;i++){
      |                ^
insects.cpp:34:16: error: 'N' was not declared in this scope
   34 |  for(int i=0;i<N;i++){
      |                ^