Project Euler Problem 1 VBScript Version

Project Euler Problem 1.vbs

Option Explicit
 
'単純に加算
Dim sum: sum = 0
Dim i
For i = 1 To 999
    If i Mod 3 = 0 Then
        sum = sum + i
    ElseIf i Mod 5 = 0 Then
        sum = sum + i
    End If
Next
WScript.Echo sum
 
'等差数列の和
sum = 0
'初項, 公差
Dim a_list: a_list = Array(3, 5, 15)
Dim a
For Each a in a_list
    Dim n: n = 999 \ a '項数
    Dim l: l = n * a   '末項 a＋(n－1)d
     
    Select Case a
        Case 3, 5: sum = sum + ((a + l) * n / 2)
        Case Else: sum = sum - ((a + l) * n / 2)
    End Select
Next
WScript.Echo sum