Submission #1130154

#	Time	Username	Problem	Language	Result	Execution time	Memory
1130154		alosza	Prisoner Challenge (IOI22_prison)	C++20	80 / 100	22 ms	1128 KiB

prison

#include "prison.h"

#include <bits/stdc++.h>

using namespace std;

const int x = 22;

string toBase3(int n)
{
	string s = "";
	while(n != 0)
	{
		s = to_string(n%3) + s;
		n /= 3;
	}
	while(s.length() < 8)
	{
		s = "0" + s;
	}
	return s;
}

vector<vector<int>> devise_strategy(int N)
{
	vector<vector<int>> res(x+1);
	for(int i = 0; i < x+1; i++)
	{
		res[i] = vector<int>(N+1);
		res[i][0] = ((i+2) / 3) % 2;
		if(i == 0)
		{
			for(int j = 1; j < N+1; j++)
			{
				string base3 = toBase3(j);
				res[i][j] = base3[0] - '0' + 1;
				//cout << res[i][j] << " ";
			}
		}
		else if(i == x)
		{
			for(int j = 1; j < N+1; j++)
			{
				string base3 = toBase3(j);
				int thisnumber = -1 - res[i][0];
				if(base3[7] == '0') res[i][j] = thisnumber;
				if(base3[7] == '2') res[i][j] = (-3 - thisnumber);
			}
		}
		else
		{
			for(int j = 1; j < N+1; j++)
			{
				string base3 = toBase3(j);
				int lastdigit = (i-1)%3;
				int numdigit = (i+2)/3;
				int digit = base3[numdigit-1] - '0';
				int thisdigit = base3[numdigit] - '0';
				int thisnumber = -1 - res[i][0];
				if(digit != lastdigit)
				{
					res[i][j] = (digit < lastdigit)? thisnumber : (-3 - thisnumber);
					//cout << res[i][j] << " ";
				}
				else
				{
					if(numdigit == 7)
					{
						if(thisdigit == 0) res[i][j] = thisnumber;
						else if(thisdigit == 2) res[i][j] = (-3 - thisnumber);
						else res[i][j] = x;
					}
					else
					{
						res[i][j] = base3[(i+2)/3] - '0' + ((i+2)/3)*3 + 1;
					}
					//cout << res[i][j] << " ";
				}
			}
		}
		//cout << "\n";
	}
	return res;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 70 / 90