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$NumberOfGamblers = 5000
$RoundsOfBetting = 5000  
$RoundsOfSimulation = 100      
$BetAmount = 10.00

class Gambler
  def initialize
    @balance = rand * 5000  # Gambler get 0 - 99.999% of $5000
    @initial = @balance     # save the inital balance
  end

  def win
    @balance += $BetAmount
  end

  def lose
    @balance -= $BetAmount
  end

  def broke
    @balance <= 0
  end

  def net
    @balance - @initial
  end
end

class Casino < Gambler                 
  # casino is a gambler with a very high balance 
  #  that never goes broke
  def initialize
    @balance = 100_000_000.00     
    @initial = @balance
  end

  def broke
    false
  end
end

def simulateCasino
  casino = Casino.new
  gamblers = []
  $NumberOfGamblers.times {gamblers << Gambler.new}

  $RoundsOfBetting.times do
    gamblers.each do |gambler|
      unless gambler.broke
        if rand(2) < 1
          $win +=1
          casino.lose
          gambler.win
        else       
          $lose+=1
          casino.win
          gambler.lose
        end
      end
    end
  end
     
  gWins = 0
  ttlGamblerWins = gamblers.each do |g|
    gWins += 1 if (g.net > 0)
  end

  puts "Casino #{casino.net < 0 ? 'lost' : 'won'} (net:#{casino.net})\n"
  puts "Winning Gamblers=#{gWins} of #{gamblers.count}\n"
  return [casino.net,gWins]
end

casinoWins = 0
$win = $lose = 0
totalCasinoNet = 0
losers = 0
winners = 0
$RoundsOfSimulation.times do 
  net,wins = simulateCasino
  totalCasinoNet += net
  casinoWins += 1 if net > 0
  losers += $NumberOfGamblers - wins
  winners += wins
end

puts "Casino won #{casinoWins} out of #{$RoundsOfSimulation} simulations"   
puts "Casino net:#{totalCasinoNet}\n"
puts "total losers:#{losers}\n"
puts "total winners:#{winners}\n"  
puts "percentage of winners:#{(winners.to_f/(winners.to_f+losers.to_f))*100.0}\n"     
puts "winning bets to losing bets:#{$win.to_f/$lose.to_f} (to evaluate overall 'fairness' of simulation bets)"