Consider a type of hexadecimal colour code that supports shorthand for both greyscale and colour:

• A 6 digit code is interpreted as 2 digits for red, followed by 2 for green, then 2 for blue.
• A 2 digit code is greyscale. The 2 digits are used for each of red, green, and blue.
• A 3 digit code is shorthand for a 6 digit code with repeated digits for red, green, and blue.
• A 1 digit code is shorthand for a 2 digit greyscale code with the same 1 digit repeated.

Input

• A colour code in the format "#" followed by 1, 2, 3, or 6 hexadecimal digits.
• You may take input as either a string or any ordered sequence data type.

Output

• A colour code in the format "#" followed by 6 hexadecimal digits.
• The output after the "#" depends on the number of hexadecimal digits in the input as follows:
  • Input with 1 digit: output the 1 digit 6 times.
  • Input with 2 digits: output the 2 digit string 3 times.
  • Input with 3 digits: output each digit twice (rather than the 3 digit string twice).
  • Input with 6 digits: output the same 6 digits.
• You may output as either a string or any ordered sequence data type.

Test cases

Test cases are in the format Input : Output.

#0 : #000000
#A : #AAAAAA
#2E : #2E2E2E
#44 : #444444
#ACF : #AACCFF
#989 : #998899
#777 : #777777
#012345 : #012345
#BBBBBB : #BBBBBB

Scoring

This is a code golf challenge. Your score is the number of bytes in your code.

Explanations are optional, but I'm more likely to upvote answers that have one.

posted about 1 month ago

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1mo ago

trichoplax‭

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