qsort.go

package main

import (
	"fmt"
	"math/rand"
	"errors"
)

func Sort(list []int) ([]int, error) {
	if len(list) < 2 {
		return nil, errors.New("Slice must contain at least two elements")
	}

	left := 0
	right := len(list) - 1

	for i := range list {
		if list[i] < list[right] {
			list[i], list[left] = list[left], list[i]
			left++
		}
	}

	list[left], list[right] = list[right], list[left]

	Sort(list[:left])
	Sort(list[left+1:])

	return list, nil
}

func main() {
	l := make([]int, 2*10)
	for i := 0; i < len(l); i++ {
		l[i] = rand.Intn(10000)
	}

	fmt.Printf("Before sorting: %v\n", l)
	Sort(l)
	fmt.Printf("After sorting: %v\n", l)
}