Tool to interpret the Deadfish, an extremely basic programming language only able to display numbers via only 4 commands.
Deadfish Language - dCode
Tag(s) : Programming Language
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Deadfish Language
Deadfish Interpreter/Decoder
Deadfish Encoder
Answers to Questions (FAQ)
What is Deadfish? (Definition)
Deadfish is a minimalist programming language created by Jonathan Todd Skinner. It runs with only four commands, does not allow user input, and only handles integer values.
How to write in Deadfish?
The deadfish is a programming language simplified to the extreme using a single memory cell (initialized at 0) and 4 functions:
| i | increments the memory cell (+1) |
| d | decrement the memory cell (-1) |
| s | square (^2) the value of the memory cell |
| o | displays the value of the memory cell |
Example: To code the number 8, it is possible to write iiiiiiiio (8 increments and output) or iisiiiio (2 increments = 2, then squared = 4, 4 increments = 8 and output) or also iisdo (3 increments = 3, then squared = 9, 1 decrement = 8 and output)
The author's C implementation says that the maximum value should be 255 and if an increment reaches 256 or a decrement reaches -1, then the value is reset to zero (but there is no provision for squaring).
How to decrypt a Deadfish code?
Deadfish is not a cipher but a programming language, so use an interpreter to launch the program and display the result.
Example: iiiso corresponds to 3 increments i (+1+1+1=3), then a squaring s (3^2=9) and display of the result o, ie the number 9
The program can only display numbers, but those can use a given nomenclature (ASCII code, A1Z26, etc.) to get a plain text.
How to recognize a Deadfish code?
Deadfish has only 4 distinct letters, by default i, s, d and o in lower case.
The amount of i and d is generally greater than the amount of o and s.
There are as many o as numbers (or characters) in the output values from the program.
The numbers obtained are usually less than 17^2 = 289.
What are the variants of Deadfish?
The XKCD site has proposed a variant with its own letters replacing i with x, s with k and o with c (d stays d).
Other letter/character variations are possible.
Due to its design and level of abstraction, Deadfish resembles the Brainfuck family of languages.
Who did create Deadfish?
Deadfish have been created by Jonathan Todd Skinne
Source code
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Deadfish Language on dCode.fr [online website], retrieved on 2025-01-30,
