A Tour of Go Exercises

maps_wordcount.go

package main

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

func WordCount(s string) map[string]int {
	wordsMap := make(map[string]int)
	
	words := strings.Fields(s)
	
	for _, v := range words {
		wordsMap[v] ++ 
	}
	
	return wordsMap
}

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

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

func WordCount(s string) map[string]int {
	wordsMap := make(map[string]int)

	words := strings.Fields(s)

	for _, v := range words {
		wordsMap[v]++
	}

	return wordsMap
}

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

}

newt_sqrt.go

package main

import (
	"fmt"
	"math"
)

func Sqrt(x float64) (z float64) {
	const DELTA = 4e-16
	const INITIAL_Z = 1.0

	z = INITIAL_Z

	step := func() float64 {
		return z - (z*z-x)/(2*z)
	}

	for zz := step(); math.Abs(zz-z) > DELTA; {
		z = zz
		zz = step()
	}
	return
}

func main() {
	fmt.Println(Sqrt(100))
	fmt.Println(math.Sqrt(100))
	fmt.Println(DELTA)
}

pic_slices.go

package main

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

func Pic(dx, dy int) [][]uint8 {
	table := make([][]uint8, dy)
	for y := 0; y < dy; y++ {
		row := make([]uint8, dx)
		for x := 0; x < dx; x++ {
			row[x] = uint8(x^y)
		}
		table[y] = row
	}
	return table
}

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

// Just for comparison - fibonacci in javascript

fib = function(numMax){
    for(var fibArray = [0,1], k=0; k<numMax; k++ ){
        x=fibArray[k] + fibArray[k+1]
        fibArray.push(x);
    }
    console.log(fibArray);
}

fib(10)