package main

import (
	"fmt"
	"os"
	"strconv"
)

func main() {
	cla := os.Args
	if len(cla) != 2 {
		fmt.Println("The program requires exactly 2 args: dist k,m")
	}
	givenD, err := strconv.ParseFloat(cla[1], 64)
	if err != nil {
		fmt.Printf("%s could not be converted to a number  %v\n", cla[1], err)
	}
	if cla[2] == "k" {
		fmt.Printf("%f kilometers is %f miles\n", givenD, (givenD * 1.602))
	} else if cla[2] == "m" {
		fmt.Printf("%f miles is %f km \n", givenD, (givenD / 1.602))
	} else {
		fmt.Printf("The second arg must be k or m, got [[%s]]\n", cla[1])
	}
}