How to implement Linux tail command in Perl

I have tried writing a Perl script to simulate Linux tail command - print last n lines from a file. This is one of the common interview questions in Perl. This can be extended to print selected lines of other Linux commands like head. It works perfectly fine.


print "\nImplements linux tail command in perl \n\n";

$file   =  $ARGV[0];
$n = $ARGV[1];
open(FILE, $file);
@arr = ;
close(FILE);
$length  = scalar(@arr);
$n = $length  - $n;

while($n<$length )
{
print $arr[$n];
$n =$n + 1;
}

Comment  below if you have a better option

Converting number into text - spellnumber excel function

It is often useful to have a function to convert numbers into words in Excel. It will be very handy in accounts. I have written an Excel macro to convert numbers into text. I have already created a macro which will convert a number in Indian system - that is ##,##,### format, to words. You can find it here 

Now I have come up with a macro which does the same thing with the western numbering system, that is 3 digits separation like ###,###,###. The dollar is used as currency, but it can be changed to any currency just by changing the text "Dollar". You can do that by finding replacing.

How to use it:
1. Download the Excel VBA macro module from here 

2. Open Excel 

3. Press Alt + F11 
    A window will open, it is called Visual Basic Editor aka VBA editor. 

4. In the VBA editor select Insert, Module. 
    A new module will be created at the left side pane, on the right side you can see a blank pane. Paste your code here 
    
    Or, alternatively, you can import the module directly
    
5. Save and go back to Excel by pressing Alt + F11

6. In the Excel worksheet, select Formula and them Insert. You will see a dialog with available functions.
    You have to browse to User Defined Functions to your macro by     name ConvertCurrencyToEnglish_spellnumber
    select and provide proper input 


Here is a video showing steps clearly 

Another version of macro for Indian number system


The latest version of SpellNumber

The latest version 4.0 of MS Excel currency converter has been released. It has the following bug fixes.

See here how to use it in your excel workbook.



It used to give the wrong result for a value between 1,99,999 to 9,99,999.



It has been fixed now in version 4.0 download the latest module here 


You can download the complete excel file here


Direct access 









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