Submission #134450

#	Time	Username	Problem	Language	Result	Execution time	Memory
134450		arthurconmy	Cave (IOI13_cave)	C++14	100 / 100	323 ms	536 KiB

cave

#include <bits/stdc++.h>
using namespace std;
 
#ifndef ARTHUR_LOCAL
	#include "cave.h"
#endif
 
#ifdef ARTHUR_LOCAL
	int tryCombination(int an_S[])
	{
		cout << "TRYING: ";
		for(int i=0; i<4; i++) cout << an_S[i] << " ";
		cout << endl;
 
		int ans=-1;
 
		if(an_S[0]!=1) ans=3;
		if(an_S[3]!=0) ans=2;
		if(an_S[1]!=1) ans=1;
		if(an_S[2]!=1) ans=0;
 
		cout << ans << endl;
		return ans;
	}
#endif
 
void exploreCave(int n)
{
	int D[n]; 
	int S[n];
 
	for(int i=0; i<n; i++)
	{
		S[i]=0;
		D[i]=0;
	}
 
	if(n==1)
	{
		if(tryCombination(S)==-1) answer(S,D);
		S[0]=1;
		answer(S,D);
	}
 
	vector<int> lock(n);
 
	for(int i=0; i<n; i++)
	{
		int l=0;
		int r=n-1; // door i is controlled by a switch in the range between l and r
 
		int now=-1;
		int cur=-1;
 
		bool first_go=1;
 
		while(l<r)
		{
			// cout << l << " " << r << endl;
 
			if(first_go)
			{
				cur = tryCombination(S);
				first_go=0;
			}
 
			else cur = now;
 
			int mid = int((l+r)/2);
 
			for(int j=l; j<=mid; j++)
			{
				if(!lock[j]) S[j]=1-S[j];
			}
 
			now = tryCombination(S);
 
			if(cur==now || (cur!=i && now!=i))
			{
				// cout << cur <<" " << now << " " << i << " " << mid << endl;
				l = mid+1;
			}
 
			else
			{
				r=mid;
			}
		}
 
		if(now == i) S[l]=1-S[l];
		lock[l]=1;
		D[l]=i;
	}
 
	answer(S,D);
}

• Subtask 1: 12 / 12
• Subtask 2: 13 / 13
• Subtask 3: 21 / 21
• Subtask 4: 30 / 30
• Subtask 5: 24 / 24