2027

2027 is a program with 2027 unique commands, and it only works in the year 2025. However, every year, the documentation is changed so that the current year is the only one that is supported in.

Commands

f_1 - Undefined behaviour, different for every interpreter.
f_2 - Ditto.
f_3 - Ditto.
...
f_2026 - Ditto.
f_2027 - Ditto.

Hello World

This only works on some interpreters

f_136

Solve the Halting Problem

This only works on some interpreters

f_777 f_3 f_4 f_999 f_100 f_8 f_32 f_33