4.正三角形

Dim i, j, k, 輸入奇數 As Integer

Console.Write("請輸入一個奇數 : ")

輸入奇數 = Console.ReadLine

'9 5 7 4 11 6 (a+1)/2

'For i = 1 To (輸入奇數 + 1) / 2

'Next

'輸入奇數=9 空=(輸入奇數-i)/2

'i=1 空=4 *=1

'i=3 空=3 *=3

'i=5 空=2 *=5

'i=7 空=1 *=7

'i=9 空=0 *=9

' For i = 1 To 輸入奇數 Step 2 '1 3 5 7 9

' Console.Write(i)

'正三角形

For i = 1 To 輸入奇數 Step 2 '1 3 5 7 9

For k = 1 To (輸入奇數 - i) / 2 '印出空格

Console.Write(" ")

Next

For j = 1 To i '印出星號*

Console.Write("*")

Next

Console.WriteLine("")

Next

'倒三角形

For i = 輸入奇數 - 2 To 1 Step -2 '9 7 5 3 1

For k = 1 To (輸入奇數 - i) / 2 '印出空格

Console.Write(" ")

Next

For j = 1 To i '印出星號*

Console.Write("*")

Next

Console.WriteLine("")

Next