Just had a 'spirited' conversation with a co-worker about the succinctness of the following BASIC statement:

10 PRINT CHR$(205.5+RND(1)); : GOTO 10

It's the title of this book, and will simply print a sequence of / and \ characters, alternating between the two randomly, resulting in a pattern similar to this:

enter image description here

(Image borrowed from http://www.flickr.com/photos/rndmcnlly/5058442151/sizes/o/in/photostream/)

Being of a PHP proclivity, we wondered what the most compact way of writing the same thing in PHP would be, and came up with this:

while(1) { echo chr(47 + 45 * rand(0,1)); }

chr(47) is a / character, and chr(92) is a \. So the statement echo chr(47 + 45 * rand(0,1)); will randomly alternate between the two, ad nauseam.

In a language of your choosing, write the shortest program or function to output an infinite random sequence of \ and / characters, where each character has an equal probability of being chosen.

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    \$\begingroup\$ You can lose the {} braces, but that's about as concise as you can make it. \$\endgroup\$
    – Michael
    Dec 7, 2012 at 16:23
  • \$\begingroup\$ This is cool. What font can be used to get a similar image? \$\endgroup\$
    – daniero
    Dec 9, 2012 at 19:24
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    \$\begingroup\$ This (picture) reminds me of the first "program" I ever wrote on my commodore 64 straight out of the manual :) ah happy days \$\endgroup\$
    – Dale
    Apr 9, 2013 at 13:31
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    \$\begingroup\$ @daniero I think the actual typeface is called Terminal, but I found it online as "Windows Command Prompt" codepen.io/nickforddesign/pen/WMqQdM?editors=0110 \$\endgroup\$
    – nickford
    Mar 5, 2018 at 20:49
  • \$\begingroup\$ What a strange coincidence that this Code Golf repo on Github happens to have the exact same challenge... github.com/noops-challenge/golfbot \$\endgroup\$ Jul 20, 2019 at 18:51

61 Answers 61

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Rust, 143 bytes, std only

use std::hash::*;fn main(){loop{print!("{}",b"/\\"[std::collections::hash_map::RandomState::new().build_hasher().finish()as usize%2]as char);}}

Attempt This Online!

This mess is because the Rust stdlib (at the time of writing) has no "proper" RNG API. So, I had to use the workaround described here to get a random number.

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