Tour of Go exercises

fibonacci.go

package main

import "fmt"

// fibonacci is a function that returns
// a function that returns an int.
func fibonacci() func() int {
	n := 0 // position of the number

	prev := 0
	next := 1

	// fibonacci number
	fib := 0

	return func() int {
		switch n {
		case 0:
			n += 1
			return 0
		case 1:
			n += 1
			return 1
		default:
			n += 1
			
			fib = next + prev

			prev = next
			next = fib
			
			return fib
		}
	}
}

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

maps.go

package main

import (
	"strings"
  
	"golang.org/x/tour/wc"
)

func WordCount(s string) map[string]int {
	words := strings.Fields(s)
	countMap := map[string]int{}

	for w := range words {
		current := words[w]
		// if it exists
		if _, ok := countMap[current]; ok {
			countMap[current] = countMap[current] + 1
		} else {
			countMap[current] = 1
		}
	}

	return countMap
}

func main() {
	wc.Test(WordCount)
}

slices.go

package main

import "golang.org/x/tour/pic"

func Pic(dx, dy int) [][]uint8 {
	im := make([][]uint8, dy) 
	
	for y := range im {
		im[y] = make([]uint8, dx)
		for x := range im[y] {
			im[y][x] = uint8(x^y)
		}
	}
	
	return im
}

func main() {
	pic.Show(Pic)
}