Simple implementation to demonstrate the Monty Hall Problem (http://en.wikipedia.org/wiki/Monty_Hall_problem)

monty_hall.go

package main

import (
	"fmt"
	"math/rand"
	"os"
	"strconv"
	"time"
)

func main() {
	count := 0
	rand.Seed(time.Now().Unix())
	max := 100
	if len(os.Args) > 1 {
		var err error
		max, err = strconv.Atoi(os.Args[1])
		if err != nil {
			fmt.Println(err)
			max = 100
		}
	}
	for i := 0; i < max; i++ {
		var choices [3]bool
		choices[rand.Int31n(3)] = true
		pick := rand.Int31n(3)
		show := (pick + 1) % 3
		if choices[show] {
			show = (show + 1) % 3
		}
		swap := (pick + 2) % 3
		if swap == show {
			swap = (swap + 1) % 3
		}
		if swap == pick {
			swap = (swap + 1) % 3
		}
		if choices[swap] {
			count++
		}
		fmt.Printf("%d: chose %d, showed %d, swapped to %d, swap worked: %v\n", i, pick, show, swap, choices[swap])
	}
	fmt.Println(count)
}