Urgent help needed with bar puzzle

Community Bar Sport
20

radman:
The odds that the krugerrand is under the ashtray I chose first is always 1:3 or 33.333%.

Unless I made a coding mistake, Monte Carlo says you have that backwards correct...

State.h

#ifndef States_h
#define States_h

typedef enum 
{
  sStart            = 0b00000000,
  sKrugerrand       = 0b00000001,
  sBarmanFlipped    = 0b00000010,
  sFirstGuess       = 0b00000100,
  sSecondGuess      = 0b00001000,
  sChangedMind      = 0b00010000,
} 
state_t;

#endif

Krugerrand.ino

#include "States.h"

void setup( void )
{
  Serial.begin( 115200 );
}

static void SetState( state_t & set, state_t element )
{
  set = (state_t)(set | element);
}

static void PrintState( state_t set )
{
  if ( set & sKrugerrand ) Serial.write('K'); else Serial.write(' ');
  if ( set & sBarmanFlipped ) Serial.write('B'); else Serial.write(' ');
  if ( set & sFirstGuess ) Serial.write('1'); else Serial.write(' ');
  if ( set & sSecondGuess ) Serial.write('2'); else Serial.write(' ');
  if ( set & sChangedMind ) Serial.write('C'); else Serial.write(' ');
}

static uint32_t Same;
static uint32_t Change;
static uint32_t Total;
static uint32_t Paydirt;

void loop( void )
{
  state_t Ashtray[3];
  uint8_t FirstGuess;
  uint8_t SecondGuess;
  uint8_t i;
  
  Ashtray[0] = sStart;
  Ashtray[1] = sStart;
  Ashtray[2] = sStart;
  
  SetState( Ashtray[random(0,3)], sKrugerrand );
  FirstGuess = random(0,3);
  SetState( Ashtray[FirstGuess], sFirstGuess );
  
  do
  {
    i = random(0,3);
  }
  while ( Ashtray[i] != sStart );
  
  SetState( Ashtray[i], sBarmanFlipped );

/*
  if ( random(0,2) == 0 )
  {
    ++Same;
    SecondGuess = FirstGuess;
    SetState( Ashtray[SecondGuess], sSecondGuess );
  }
  else
*/
  {
    ++Change;
    for ( int8_t i=0; i < 3; ++i )
    {
      if ( (Ashtray[i] & (sBarmanFlipped | sFirstGuess)) == 0 )
      {
        SecondGuess = i;
        SetState( Ashtray[SecondGuess], sSecondGuess );
        SetState( Ashtray[SecondGuess], sChangedMind );
        break;
      }
    }
  }
  
  for ( int8_t i=0; i < 3; ++i )
  {
    if ( (Ashtray[i] & (sKrugerrand | sSecondGuess | sChangedMind)) == (sKrugerrand | sSecondGuess | sChangedMind) )
    {
      ++Paydirt;
      break;
    }
  }

  ++Total;

/*
  for ( int8_t i=0; i < 3; ++i )
  {
    PrintState( Ashtray[i] );
    Serial.write( '\t' );
  }
*/

  if ( (Total & 0x000000FF) == 0 )
  {
/*
    Serial.print( (Same * 1000) / Total );
    Serial.write( '\t' );
*/
    Serial.print( (Paydirt * 1000) / Total );
    Serial.println();
  }
}