One geeky afternoon at work, we challenged each other to write the smallest possible program in any language to print a diamond made out of numbers, from 1 to a maximum of 9.

For example a diamond of 1 would just be 1.

A diamond of 2 would be:

 1 
121
 1
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A diamond of 3 would be:

   1
  121
 12321
  121
   1
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One of them wrote several lines of c# code. Another wrote a really long one line of code that had predefined outputs. So I entered the prizeless contest, and I decided to use Perl.

I'm sure there is a way to make a long and ugly one liner out of this, but I wanted to share what I came up with after reading chapter 1 and 2 of Learning Perl.

Enjoy!

#!/usr/bin/perl

print 'Diamond size (1-9): ';
chomp($diamondSize = <STDIN>);

foreach $i(@i = (1..$diamondSize, reverse (1..$diamondSize-1))) {
        print ' ' x ($diamondSize - $i), (@d ="1".."$i"), (reverse @d[
+0..$#d-1]),  "\n";
}
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