Diamonds for fun

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
[download]

A diamond of 3 would be:

   1
  121
 12321
  121
   1
[download]

And you get the idea for all the way up to 9...

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";
}
[download]

Comment on Diamonds for fun Select or Download Code

Replies are listed 'Best First'.
Re: Diamonds for fun by BrowserUk (Patriarch) on Mar 05, 2011 at 11:10 UTC
Golf:68. How to get rid of those reverses? `perl -E"$n=pop;say' 'x($n-$_),1..$_,reverse 1..$_-1for 1..$n,reverse 1 +..$n-1" 9` [download] Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]
Re^2: Diamonds for fun by a (Friar) on Mar 06, 2011 at 00:15 UTC
Had to: `perl -e '$n=pop; print "\n", " "x($n-$_),1..$_,reverse 1..$_-1, for 1. +.$n,reverse 1..$n-1' 9` [download] for 5.8 ish ... seems like there's a marvelous recursive solution but my brain is too small to find it. a	[reply] [d/l]
Re^2: Diamonds for fun by LanX (Saint) on May 04, 2011 at 16:22 UTC
Golf:56 :) `perl -E'$_=pop;sub r{1..$_,reverse 1..$_-1}say" "x(9-$_),r for r' 9 1 121 12321 1234321 123454321 12345654321 1234567654321 123456787654321 12345678987654321 123456787654321 1234567654321 12345654321 123454321 1234321 12321 121 1` [download] Cheers Rolf	[reply] [d/l]
Re^3: Diamonds for fun by Tux (Canon) on May 04, 2011 at 17:23 UTC
Combining with other posts here, golf:55 `perl -E'$_=pop;sub r{1..$_,reverse 1..$_-1}say$"x(9-$_),r for r' 9` Enjoy, Have FUN! H.Merijn	[reply] [d/l]
Re: Diamonds for fun by ambrus (Abbot) on Mar 07, 2011 at 14:13 UTC
I'm quite sure this can be golfed further, but as it seems shorter than the above solutions I must post it. `perl -le 'printf"%s\n",$t+$_,(1x$_)2for(1x($t=pop))2=~/./g' 9` [download] Update:* see also Christmas Tree. Update: one character shorter: `perl -e 'printf"%s\n",$t+$_,(1x$_)2for(1x($t=pop))2=~/./g' 9` [download] Somewhat shorter: `perl -le 'print" "x($t-$_),(1x$_)2for(1x($t=pop))2=~/./g' 9` [download] Update* 2012-03-14: and see Spiraling integers for yet another arrangement of numbers.	[reply] [d/l] [select]
Re^2: Diamonds for fun by toolic (Bishop) on Mar 07, 2011 at 14:45 UTC
You can shave 3 off your lowest score using perl 5.10: `# score = 53 # 1 2 3 4 5 # 12345678901234567890123456789012345678901234567890123456789 perl -E'say" "x($t-$_),(1x$_)2for(1x($t=pop))2=~/./g' 9` [download] update due to hbm's observation: `# score = 52 # 1 2 3 4 5 # 12345678901234567890123456789012345678901234567890123456789 perl -E'say$"x($t-$_),(1x$_)2for(1x($t=pop))2=~/./g' 9` [download]	[reply] [d/l] [select]
Re^2: Diamonds for fun by hbm (Hermit) on Mar 07, 2011 at 20:38 UTC
Squaring a string of ones (`(1x$_)2`) is very clever! This works for me up to 8, but 9 fails (because `1111111112 = 1.23456789876543e+16`). (Same for toolic's solution below...) You can save one more character with `$"` instead of `" "`.	[reply]
Re^3: Diamonds for fun by ambrus (Abbot) on Mar 07, 2011 at 21:14 UTC
It works for 9 on a 64 bit system, which is why I didn't notice it's broken, but it is indeed broken on 64 bit systems. You could try to fix it with something like this, but as is that's too long and I don't feel much like golfing it now. `perl -e 'printf"%.0f\n",$t+abs,(1x abs)*2for 1..($t=pop),1-$t..-1' 9` [download]	[reply] [d/l]
Re: Diamonds for fun by repellent (Priest) on Mar 06, 2011 at 09:26 UTC
Golfed at 83. `perl -E'$n=pop;say$x[@x]=$p=" "x($n-$_).(1x(2$_-1)+$p10)for 1..$n;sa +y for@x[map-$_,2..@x]' 9` [download]	[reply] [d/l]
Re: Diamonds for fun by ambrus (Abbot) on Oct 20, 2012 at 19:52 UTC
See also http://codegolf.stackexchange.com/questions/8696/print-this-diamond for the same question.	[reply]
Re: Diamonds for fun by LanX (Saint) on May 04, 2011 at 12:35 UTC
`perl -e'$"="";$x=pop;@x=reverse(1..$x);print " "x($x-$_),"@x[@x[1..$_] +]@x[$x+1-$_..$x]\n"for@x[@x],@x' 9 1 121 12321 1234321 123454321 12345654321 1234567654321 123456787654321 12345678987654321 123456787654321 1234567654321 12345654321 123454321 1234321 12321 121 1` [download] could be shortened! have fun deobfuscating! :) Cheers Rolf	[reply] [d/l]

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