Monty Hall problem with Monte Carlo solution.jl

simulations = 100000
GOAT = 0
CAR = 1
REMOVED = -1





#========================Aux functions======================#
function getremoved_door(usr,doorset)
    removed_door = -1
        for i in keys(doorset)
            if (i!=usr && doorset[i]!= CAR)
                removed_door = i
            end
        end
    return removed_door
end

function getavailable_door(usr,removed)
    available  = -1
    for i=1:3
        if (i!=usr && i!= removed)
            available = i
        end
    end

    return available
end

function changedoor(current_door::Int, available_door::Int, change::Bool)
    if change
        return available_door
    else
        return current_door
    end
end

function simulate(change::Bool)
    doors =  Dict(1=>GOAT,2=>GOAT,3=>GOAT)
    doors[rand(1:3)] = CAR
    user_door = rand(1:3)

    removed_door = getremoved_door(user_door,doors)
    delete!(doors,removed_door)

    available_door = getavailable_door(user_door,removed_door)
    user_door = changedoor(user_door,available_door,change)


    if(doors[user_door] == CAR)
        return 1
    else
        return 0
    end
end

#============================================================#
changer_cookies = 0
not_changer_cookies = 0


for i=1:simulations

    changer = simulate(true)
    not_changer = simulate(false)

    if changer == 1
        changer_cookies +=1
    end

    if not_changer == 1
        not_changer_cookies +=1
    end

    if (mod(i,5000) == 0)
        info("$i simulations executed")
        info("The changer agent scored $changer_cookies times (",round(100*changer_cookies/i,2),"%)")
        info("The not changer agent scored $not_changer_cookies times (",round(100*not_changer_cookies/i,2),"%)")
        println()
    end
end





#===================If the player never changes the door=================#

#=
not_changingwins = 0
for i=1:simulations
    not_changingwins += simulate(false)
end

info("$simulations simulations executed  by NEVER changing the door\n$not_changingwins games out of $simulations won")
println("Expected optimial result: ",round((1/3) * 100,2),"% ")
println("Matched result: ",round((not_changingwins/simulations)*100,2),"% \n")



#===================If the player always changes the door=================
changingwins = 0
for i=1:simulations
    changingwins += simulate(true)
end

info("$simulations simulations executed  by ALWAYS changing the door\n$changingwins games out of $simulations won")
println("Expected optimial result: ",round((2/3) * 100,2),"% ")
println("Matched result: ",round((changingwins/simulations)*100,2),"% \n")
=#