Source code in the phix programming language

function play(integer prisoners, iterations, bool optimal)
    sequence drawers = shuffle(tagset(prisoners))
    integer pardoned = 0
    bool found = false
    for i=1 to iterations do
        drawers = shuffle(drawers)
        for prisoner=1 to prisoners do
            found = false
            integer drawer = iff(optimal?prisoner:rand(prisoners))
            for j=1 to prisoners/2 do
                drawer = drawers[drawer]
                if drawer==prisoner then found = true exit end if
                if not optimal then drawer = rand(prisoners) end if
            end for
            if not found then exit end if
        end for
        pardoned += found
    end for
    return 100*pardoned/iterations
end function
 
constant iterations = 100_000
printf(1,"Simulation count: %d\n",iterations)
for prisoners in {10,100} do
    atom random = play(prisoners,iterations,false),
         optimal = play(prisoners,iterations,true)
    printf(1,"Prisoners:%d, random:%g, optimal:%g\n",{prisoners,random,optimal})
end for