The Selection Sorting Algorithm in VBScript

  • 时间：2020-09-17 14:26:24
  • 分类：网络文摘
  • 阅读：133 次

The selection sort, similar to insertion sort, is one of the simple sorting algorithm that has O(N^2) time complexity. The selection sorting algorithm is quadratic, thus not efficient when the items to sort is large.

The selection sort works by choosing a minimal element in the unsorted list and append the element to the sorted list – which is done by swapping the element beyond the end of the sorted part.

For example, given the array: [3, 5, 2, 6, 1, 3, 4, 6, 9], we can simulate the Selection Sort algorithm in the following process:

1
2
3
4
5
6
7
8
9
10

Sorted: [] Unsorted: [3, 5, 2, 6, 1, 3, 4, 6, 9] // min = 1 in the Unsorted
Sorted: [1, ] Unsorted: [3, 5, 2, 6, 3, 4, 6, 9] // min = 2 in the Unsorted
Sorted: [1, 2] Unsorted: [3, 5, 6, 3, 4, 6, 9] // min = 3 in the Unsorted
Sorted: [1, 2, 3] Unsorted: [5, 6, 3, 4, 6, 9] // min = 3 in the Unsorted
Sorted: [1, 2, 3, 3] Unsorted: [5, 6, 4, 6, 9] // min = 4 in the Unsorted
Sorted: [1, 2, 3, 3, 4] Unsorted: [5, 6, 6, 9] // min = 5 in the Unsorted
Sorted: [1, 2, 3, 3, 4, 5] Unsorted: [6, 6, 9] // min = 6 in the Unsorted
Sorted: [1, 2, 3, 3, 4, 5, 6] Unsorted: [6, 9] // min = 6 in the Unsorted
Sorted: [1, 2, 3, 3, 4, 5, 6, 6] Unsorted: [9] // min = 9 in the Unsorted
Sorted: [1, 2, 3, 3, 4, 5, 6, 6, 9] Unsorted: [] // Done.
Sorted: [] Unsorted: [3, 5, 2, 6, 1, 3, 4, 6, 9] // min = 1 in the Unsorted
Sorted: [1, ] Unsorted: [3, 5, 2, 6, 3, 4, 6, 9] // min = 2 in the Unsorted
Sorted: [1, 2] Unsorted: [3, 5, 6, 3, 4, 6, 9] // min = 3 in the Unsorted
Sorted: [1, 2, 3] Unsorted: [5, 6, 3, 4, 6, 9] // min = 3 in the Unsorted
Sorted: [1, 2, 3, 3] Unsorted: [5, 6, 4, 6, 9] // min = 4 in the Unsorted
Sorted: [1, 2, 3, 3, 4] Unsorted: [5, 6, 6, 9] // min = 5 in the Unsorted
Sorted: [1, 2, 3, 3, 4, 5] Unsorted: [6, 6, 9] // min = 6 in the Unsorted
Sorted: [1, 2, 3, 3, 4, 5, 6] Unsorted: [6, 9] // min = 6 in the Unsorted
Sorted: [1, 2, 3, 3, 4, 5, 6, 6] Unsorted: [9] // min = 9 in the Unsorted
Sorted: [1, 2, 3, 3, 4, 5, 6, 6, 9] Unsorted: [] // Done.

Translating to VBScript, we have the following Selection Sorting Algorithm:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22

Dim Nums: Nums = Array(3, 5, 2, 6, 1, 3, 4, 6, 9)
 
Sub SelectionSort(ByRef Nums)
    For i = LBound(Nums) To UBound(Nums) - 1
        Dim min: min = i
        For j = i + 1 To UBound(Nums)
            If Nums(j) < Nums(min) Then
                min = j
            End If 
        Next
        If min <> i Then
            Dim t: t = Nums(min)
            Nums(min) = Nums(i)
            Nums(i) = t
        End If
    Next
End Sub
 
SelectionSort Nums
For i = LBound(Nums) To UBound(Nums) 
    WScript.Echo Nums(i)
Next
Dim Nums: Nums = Array(3, 5, 2, 6, 1, 3, 4, 6, 9)

Sub SelectionSort(ByRef Nums)
	For i = LBound(Nums) To UBound(Nums) - 1
		Dim min: min = i
		For j = i + 1 To UBound(Nums)
			If Nums(j) < Nums(min) Then
				min = j
			End If 
		Next
		If min <> i Then
			Dim t: t = Nums(min)
			Nums(min) = Nums(i)
			Nums(i) = t
		End If
	Next
End Sub

SelectionSort Nums
For i = LBound(Nums) To UBound(Nums) 
	WScript.Echo Nums(i)
Next

One advantage of Selection Sorting Algorithm is that it has at most (n-1) swaps when sorting n elements.

--EOF (The Ultimate Computing & Technology Blog) --

推荐阅读：
为 WordPress 主题添加大红灯笼特效　 为 wordpress 文章作者在评论留言时显示“本文作者”提示　 为 WordPress 主题添加花瓣飘落特效　 wordpress插件：WP-China-Yes 切换WP站点与官方通信至国内节点解决后台更新429错误　 一段代码轻松解决wordpress定时发布失败的问题　 WordPress官网打不开 出现 429 Too Many Request 的原因　 下载更新wordpress程序及插件的方法　 禁用wordpress4.4+版本自动生成768w像素缩略图功能　 自动为wordpress文章图片添加alt属性和title属性　 如何为WordPress导航菜单、标签、出站等链接添加nofollow标签属性　
评论列表
添加评论