1 package qsort
 2 
 3 func quickSort(values []int, left,right int) {
 4   temp := values[left]
 5   p := left
 6   i,j := left,right
 7 
 8   for i<=j {
 9     for j >= p && values[j] >= temp {
10       j-- 
11     }   
12     if j >= p { 
13       values[p] = values[j]
14       p = j 
15     }   
16 
17     for i <= p && values[i] <= temp {
18       i++ 
19     }   
20     if i <= p { 
21       values[p] = values[i]
22       p = i 
23     }   
24   }
25   values[p] = temp
26   if p - left > 1 { 
27     quickSort(values, left, p-1)
28   }
29   if right - p > 1 { 
30     quickSort(values, p+1, right)
31   }
32 }
33 
34 func QuickSort(values []int) {
35   quickSort(values, 0, len(values)-1)
36 }

 1 package qsort
 2 
 3 import "testing"
 4 
 5 func TestQuickSort1(t *testing.T) {
 6   values := []int{5,4,3,2,1}
 7   QuickSort(values)
 8   if values[0] != 1 || values[1] != 2 || values[2] != 3 || values[3] != 4 || values[4] != 5 { 
 9     t.Error("QuickSort() failed. Got", values, "Expected 1 2 3 4 5")
10   }
11 }

 1 package bubblesort
 2 
 3 func BubbleSort(values []int) {
 4   flag := true
 5 
 6   for i:=0; i<len(values); i++ {
 7     flag = true
 8 
 9     for j:=0; j<len(values)-i-1; j++{
10       if values[j] > values[j+1] {
11         values[j],values[j+1] = values[j+1],values[j]
12         flag = false
13       }   
14     }   
15 
16     if(flag == true) {
17       break
18     }   
19   }
20 }

 1 package bubblesort
 2 
 3 import "testing"
 4 
 5 func TestBubbleSort1(t *testing.T) {
 6   values := []int{5,4,3,2,1}
 7   BubbleSort(values)
 8   if values[0]!=1 || values[1]!=2 || values[2]!=3 || values[3]!=4 || values[4]!=5 {
 9     t.Error("BubbleSort() failed.Got", values, "Expected 1 2 3 4 5.")
10   }
11 }

 1 package main
 2 
 3 import (
 4   "fmt"
 5   "flag"
 6   "bufio"
 7   "io"
 8   "os"
 9   "strconv"
10   "time"
11   "sorter/algorithm/qsort"
12   "sorter/algorithm/bubblesort"
13 )
14 
15 var infile *string = flag.String("i", "unsorted.dat", "File contains values for sorting")
16 var outfile *string = flag.String("o", "sorted.dat", "File to receive sorted values")
17 var algorithm *string = flag.String("a", "qsort", "Sort algorithm")
18 
19 func readValues(infile string)(values []int, err error) {
20   file, err := os.Open(infile)
21   if err != nil {
22     fmt.Println("Failed to open the input file ", infile)
23     return
24   }
25 
26   defer file.Close()
27 
28   br := bufio.NewReader(file)
29   values = make([]int, 0)
30 
31   for  {
32     line, isPrefix, errl := br.ReadLine()
33 
34     if errl != nil {
35       if errl != io.EOF {
36         err = errl
37       }
38       break
39     }
40 
41     if isPrefix {
42       fmt.Println("A too long line, seems unexpected.")
43       return
44     }
45 
46     str := string(line)
47     value, errl := strconv.Atoi(str)
48     if errl != nil {
49       err = errl
50       return
51     }
52     values = append(values, value)
53   }
54   return
55 }
56 
57 func writeValues(values []int, outfile string) error {
58   file, err := os.Create(outfile)
59   if err != nil {
60     fmt.Println("Failed to create the output file ", outfile)
61     return err
62   }
63 
64   defer file.Close()
65 
66   for _,value := range values {
67     str := strconv.Itoa(value)
68     file.WriteString(str + "\n")
69   }
70   return nil
71 }
72 
73 func main() {
74   flag.Parse()
75   if infile != nil {
76     fmt.Println("infile=", *infile, "outfile=", *outfile, "algorithm=", *algorithm)
77   }
78 
79   values, err := readValues(*infile)
80   if err == nil {
81     fmt.Println("Read values: ", values)
82     t1 := time.Now()
83     switch *algorithm {
84       case "qsort" :
85         qsort.QuickSort(values)
86       case "bubblesort":
87         bubblesort.BubbleSort(values)
88       default:
89         fmt.Println("Sorting algorithm", *algorithm, "is either unknown or unsupported.")
90     }
91     t2 := time.Now()
92 
93     fmt.Println("The sorting process costs", t2.Sub(t1), "to cpmplete")
94 
95     writeValues(values, *outfile)
96   }else {
97     fmt.Println(err)
98   }
99 }