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hacking.md

@@ -55,7 +55,7 @@ A great many commonly used tricks in programming could be regarded as hacks even
 - **[bit hacks](bit_hack.md)**: Clever manipulations of [bits](bit.md) -- for example it is possible to swap two variable without a temporary variables by using the [xor](xor.md) function. Another simplest example is implementing division by 2 as binary shift by 1 (this hack is used in real life by people for quickly dividing by 10, we just remove the last digit).
 - **[copyleft](copyleft.md)**: A legal hack by [Richard Stallman](rms.md), connected to [free software](free_software.md), working on the basis of the following idea: "If [copyright](copyright.md) lets me put any conditions on my work, I may impose a condition on my work that says that any modified version must not impose any restrictive conditions".
 - In minimalist [C](c.md) programming mainly two standards of the language are used: C89 and C99. To distinguish between them in source code one can e.g. exploit the fact that C99 introduced line comments (starting with `//`) and make such code that C99 sees part of it commented out while C89 doesn't. For example the following two lines: `int isC89 = 1 //**/ 2`, `; isC89 = !isC89;`.
-- **[fast inverse square root](fast_inverse_sqrt.md)**: Famous hack that was used in the [game](game.md) Quake, it [approxmates](approximation.md) an inverse of [square root](sqrt.md) of a [floating point](float.md) number by treating it as an integer and bashing it with a [magic constant](magic_constant.md), which is about four times faster than computing the value with the obvious floating point division.
+- **[fast inverse square root](fast_inverse_sqrt.md)**: Famous hack that was used in the [game](game.md) Quake, it [approximates](approximation.md) an inverse of [square root](sqrt.md) of a [floating point](float.md) number by treating it as an integer and bashing it with a [magic constant](magic_constant.md), which is about four times faster than computing the value with the obvious floating point division.
 - **memory [rape](rape.md) in [C](c.md)**: E.g. instead of doing proper memory allocation with potentially inefficient and bloated `malloc` one may try to do a custom memory allocation without any libraries by abusing allocation on stack -- allocate a variable size array in main, set some global pointer to it and then manage this chunk of memory with your own allocation functions.
 - **actually portable executable** (https://justine.lol/ape.html): Justine Tunney found a way to create an executable format that passes as a valid NATIVE executable on all major systems including [GNU](gnu.md)/[Linux](linux.md), [Windows](windows.md) and [Mac](mac.md), i.e. it is possible to compile a native program (e.g. with [C](c.md)) and then have it natively run on any major OS.
 - **[game of life](game_of_life.md) patterns**: Stable patterns such as glider or even programming game of life in game of life is a nice example of game hacking -- in fact exactly game of life hacking stood at the beginning of hacker culture.