go算法练习

冒泡排序：

package main

import(
    "fmt"
)

// 1, 38, 4, 5, 10
// 1, 4, 38, 5, 10
// 1, 4, 5, 38, 10
// 1, 4, 5, 10, 38
//冒泡排序
func bubble_sort(a []int) {

    for i := len(a)-1; i > 0; i-- {
        for j := 0; j < i; j++ {
            if a[j] > a[j+1] {
                a[j], a[j+1] = a[j+1], a[j]
            }
        }
    }
}

func main() {
    a := []int{38, 1, 4, 5, 10}
    bubble_sort(a)        
    fmt.Println(a)
}

选择排序：

package main

import(
    "fmt"
)

//38, 1, 4, 5, 10
//1, 38, 4, 5, 10
//1, 4, 38, 5, 10
//选择排序
func select_sort(a []int) {
    for i := 0; i < len(a)-1; i++ {
        for j := i+1; j < len(a);j++ {
            if a[j] < a[i] {
                a[j], a[i] = a[i], a[j]
            }
        }
    }
}

func main() {
    a := []int{38, 1, 4, 5, 10}
    select_sort(a)
    fmt.Println(a)
}

插入排序：

package main

import(
    "fmt"
)


//38, 1, 4, 5, 10
//38
//1, 38, 
//1, 4, 38,
//1, 4, 5, 38,
//1, 4, 5, 10, 38
//插入排序
func insert_sort(a []int) {
    for i := 1; i < len(a); i++ {
        for j := i;j > 0;j-- {
            if a[j] < a[j-1] {
                a[j], a[j-1] = a[j-1], a[j]
            } else {
                break
            }
        }
    }
}

func main() {
    a := []int{38, 1, 4, 5, 10}    
    insert_sort(a)
    fmt.Println(a)
}

快速排序：

package main

import(
    "fmt"
)

//50, 100, 4, 5, 10, 50
//10, 100, 4, 5, 38, 50
//10, 38, 4, 5, 100, 50
//10, 4, 38, 5, 100, 50
//10, 4, 5, 38, 100, 50
//5, 4, 10,
//4, 5, 10, 38, 
func partion(a []int, left, right int) int {
    var i = left
    var j = right
    for i < j {
        for j > i && a[j] > a[left] {
            j--
        }
        a[j], a[left] = a[left], a[j]
        for i < j && a[i] < a[left] {
            i++
        }
        a[left], a[i] = a[i], a[left]
        fmt.Println(i)
    }
    return i
}

func qsort(a []int, left, right int) {
    if left >= right {
        return
    }

    mid := partion(a, left, right)
    qsort(a, left, mid-1)
    qsort(a, mid+1, right)
}

func main() {
    a := []int{38, 1, 4, 5, 10}
    qsort(a, 0, len(a)-1)
    fmt.Println(a)
}