exercise-fibonacci-closure.go

package main

import "fmt"

// fibonacci is a function that returns
// a function that returns an int.
func fibonacci() func() int {
	numbers := make([]int, 2)
	
	return func() int {
		lastNumber := numbers[1]

		numbers[1] = numbers[0] + lastNumber
		numbers[0] = numbers[1] - numbers[0]

		if numbers[0] == 0 {
			numbers[1] = 1
		}

		return lastNumber
	}
}

func main() {
	f := fibonacci()
	for i := 0; i < 10; i++ {
		fmt.Println(f())
	}
}