A decidely non-challenging task to highlight a potential difference between programming languages.

Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may be 2,5 for zero-based or 3,6 if one-based. 

The purpose is to determine whether variable declaration (in block scope) resets the contents on every iteration.

There is no particular judgement of right or wrong here, just a plain-speaking statement of subtle differences.

Should your first attempt bomb with "unassigned variable" exceptions, feel free to code it as (say)

 // int prev // crashes with unassigned variable
    int prev = -1 // predictably no output

If your programming language does not support block scope (eg assembly) it should be omitted from this task.

Option Strict On
Option Explicit On
 
Imports System.IO
 
Module vMain
 
    Public Sub Main
        Dim s As Integer() = New Integer(){1, 2, 2, 3, 4, 4, 5}
        For i As Integer = 0 To Ubound(s)
            Dim curr As Integer = s(i)
            Dim prev As Integer
            If i > 1 AndAlso curr = prev Then
                  Console.Out.WriteLine(i)
            End If
            prev = curr
        Next i
    End Sub
 
End Module