Simplified parse.

collatz/calculator.go

@@ -25,11 +25,10 @@ func NewCalculator(parser *io.Cliargs) Calculator {
 }
 
 func (o Calculator) Collatz() {
-	err := o.parser.Parse()
+	number, err := o.parser.Parse()
 	if err != nil {
 		log.Panicf("Couldn't parse input: %s\n", err)
 	}
-	number := o.parser.GetNumber()
 	fmt.Print(number.Text(10))
 	o.nextNumber(number)
 	fmt.Println()