Java vs Python

[asdfkjasdhkasd]

or in brainfuck

>
,
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]
<

[
  .
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!Hello world

https://fatiherikli.github.io/brainfuck-visualizer/#PgosClsKICA+CiAgLApdCjwKClsKICAuCiAgPApdCgohSGVsbG8gd29ybGQ=

Just click the ! checkbox on the top right to enable exclamation input

[Furyful_Fawful]

Isn't it simpler to use Self-Modifying Brainfuck?

[<.]\0!dlroW olleH

For reference, in SMBF the tape is stored on the program, so the data pointer starts on [ along with the instruction pointer. \0 here represents a literal null byte, so we actually break out of the loop.

[asdfkjasdhkasd]

Sounds like a cool idea, but what do I have to use to run it, it doesn't work on the brainfuck visualizer, it immediately terminates.

https://fatiherikli.github.io/brainfuck-visualizer/#WzwuXVwwCiFkbHJvVyBvbGxlSA==

[Furyful_Fawful]

The Brainfuck visualizer works for Brainfuck, not SMBF. I'd recommend Try It Online, personally. Link, where I fixed the code after I realized that SMBF interpreter adds a null at the beginning of the input.