26 votes
Accepted

Converting "0xUsernames"

05AB1E, 4 bytes D1ìH Explanation ...
  • 1,338
26 votes

Swap the Endianness

x86_32 machine language, 3 bytes endian_swap: # to be called with PASCAL REGISTER calling convention 0f c8 bswap eax c3 ret This is a bit of a ...
  • 4,448
22 votes
Accepted

Numbers that are actually letters

Pyth, 43 - 40 = 3 bytes ?&K@J.HQG-JG"Mix"%"Only %sers"?K"lett""numb Test suite This achieves the bonus. Only numbers and ...
  • 41.5k
20 votes

Magic popcount numbers

Python 2, 52 49 46 bytes The kth number is given by 2**512/(2**2**k + 1). This is for a 512 bit number, so it's trivial to extend the pattern to different widths. ...
  • 38.8k
19 votes

Converting "0xUsernames"

JavaScript (ES6), 15 bytes s=>'0x1'+s-0||s How it works '0x1'+s converts the input into a literal hexadecimal string with ...
16 votes

RGB to hexadecimal

Python 3, 22 bytes ("#"+"%02x"*3).__mod__ Try it online! Takes inputs as a tuple. The idea is to avoid a ...
  • 140k
15 votes

Numbers that are actually letters

Pyth, 6 bytes !-.HQG .HQ # Converts the input to hexadecimal - G # Deletes all letters ! # If empty, output True, else False Test it here
  • 43.7k
15 votes

Let's golf a BIBABOBU decoder

05AB1E, 36 35 33 bytes Saved 1 byte thanks to Mr.Xcoder Saved 2 bytes thanks to KevinCruijssen ć©¡®ì®D…IAO©â'D«‚˜®'U«âJskh2ôJHçJ Try it online! or as a Test ...
  • 52.3k
14 votes

Convert a number to Hexadecimal

Turing Machine Code, 412 bytes As usual, I'm using the rule table syntax defined here. You can test it on that site or, alternatively, using this java implementation. ...
  • 11.8k
14 votes

Print the f × f times table

Jelly, 12 bytes ⁴Ḷ×þ`d⁴‘ịØhG Try it online! How it works ...
  • 208k
14 votes

Print the f × f times table

Python 2, 60 bytes for n in range(256):r=n%16;print'%02x%s'%(n/16*r,r/15*'\n'), Try it online! How it works For all integers n from 0 to 255, we do the following. ...
  • 208k
14 votes

Let's golf a BIBABOBU decoder

Jelly, 26 24 23 22 20 17 15 bytes ṣḢO^1%9%4Ḅḅ⁴b⁹Ọ Try it online! How it works ...
  • 208k
13 votes
Accepted

Hexadecimal and the Alphabet

Jelly, 18 bytes b⁴µ:⁵©+¹%⁵ḅ⁵ß¹®S¤? Try it online! The binary, 18 byte version of the source code has the xxd dump ...
  • 208k
13 votes
Accepted

Output the HTML colors

Jelly, 31 29 27 bytes “×Ɗ¡‘ŒP»Ṫ¦209ṗ€3Fd⁴ịØHs3ṢQY Try it online! How it works “×Ɗ¡‘ yield the code points of the characters ...
  • 208k
13 votes

Better Hex Color Codes for Your Internet

JavaScript, 86 82 77 bytes x=>([s,a=0,b=a,c,d,e,f]=x,f?x:e?x+e:[s,a,d||a,c?b:a,d||b,v=c||b,d||v].join``) just find out that remove recursive save 4 bytes... ...
  • 30.9k
13 votes

Let's golf a BIBABOBU decoder

Perl 6, 58 bytes {S:g{(B.[D.]?)**2}=chr :16[$0».&{:2[.ords»³X%87 X%4]}]} Try it online! Heavily inspired by Dennis' Jelly solution. Uses a different magic ...
  • 10.5k
13 votes

Code Golf Measurer © 2019

tcsh, 12 bytes xxd -r|wc -c Try it online!
13 votes

Code Golf Measurer © 2019

Retina 0.8.2, 8 bytes .{51} . Try it online! Explanation: .{51} Delete the first 51 characters of each line. (Lines can ...
  • 150k
13 votes

Reverse hex cipher

Vyxal s, 5 bytes CHRHC Try it Online! Look ma, no unicode, and it's a palindrome! ...
  • 32.7k
12 votes

Numbers that are actually letters

Jelly, 6 bytes b16>9P Try it online! How it works ...
  • 208k
12 votes

Convert xxd output to shellcode

Bash + coreutils + xxd, 73 71 69 bytes printf \\x%s `xxd -r|xxd -p -s0x$1 -l$[(e=1+0x$2)?e-0x$1:-1]|fold -2` Expects the hexdump on STDIN and start/end as ...
  • 208k
12 votes
Accepted

Convert to Bibi-binary

05AB1E, 20 18 16 bytes hv…ÂkdžM¨ÁâyHèJ Explanation ...
  • 52.3k
12 votes

Convert to Bibi-binary

Python 2, 58 bytes f=lambda n:(n>15and f(n/16)or"")+"HBKD"[n/4%4]+"OAEI"[n%4] A recursive solution. Try it on Ideone.
  • 8,050
12 votes

Hexadecimal -> Binary Art

Excel (ms365), 74, 72, 59 bytes -13 Byte thanks to @jdt =SUBSTITUTE(SUBSTITUTE(HEX2BIN(0&A1:A4,8),"0"," "),"1","X") ...
  • 1,271
11 votes

Numbers that are actually letters

TeaScript, 11 bytes 13 15 16 xT(16)O(Sz) Pretty simple. This uses TeaScript 2.0. You can get this version from the Github Explanation ...
  • 28.6k
11 votes

Output the HTML colors

Bash + GNU Utilities, 67 2 bytes saved thanks to @manatwork 2 bytes saved thanks to @zeppelin a={00,80,FF} eval echo $a$a$a|fmt -w9|sed '16iC0C0C0 /F0*8\|80*F/d' ...
11 votes

Print the f × f times table

R, 42 bytes as.hexmode(sapply(0:15,function(x)x*0:15)) Prints the following: ...
  • 2,984
11 votes

Hexadecimal -> Binary Art

Ruby -p, 40 31 bytes Takes input on stdin separated by newlines. $_=("%08b "%$_.hex).tr"01"," X" ...
  • 8,566
10 votes

Numbers that are actually letters

Python, 24 bytes lambda n:min('%x'%n)>'9' Converts the input a hex string (without 0x prefix) with ...
  • 140k
10 votes

Print the f × f times table

Bash + coreutils, 40 1 byte saved thanks to @MitchellSpector printf %02x\ $[{0..15}*{0..15}]|fmt -52 Bash expands brace expansions before arithmetic expansions,...

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