Hey it could be worst, i know how to use it and still used it wrong .-.

Just as I clicked submit, I envivisioned (as I usually do) what the one line solution would look like and just as I thought of abs(), here it is. Dammit.

Poor guy, lol

I mean runtime because of an additional function call.

What do you mean by expensive? As in it takes a lot of system resources compared to over operations?

I am not sure where Codewars rules say thay you need to be as fast as possible :)

i mean, codewars is sbout doing it as fast as possible, even if its extremely ugly

-0 == 0 == +0, try it in the interpreter

Nice!

Just stop.

It's rather a function that can be called on a list to return it's length. But it is not exclusive to lists, can be used on many different types of objects.

How to do formatting

It does not matter. Any modern C compiler can optimize abs(x) and x < 0 ? -x : x equally. gcc 12 compiles both into the exact same code sequence.

sh-5.2$ cat foo.c
#include <stdlib.h>

int f(int x) {
  return abs(x);
}
int g(int x) {
  return x < 0 ? -x : x;
}

sh-5.2$ gcc -O2 -S foo.s
sh-5.2$ cat foo.s
.file	"foo.c"
	.text
	.p2align 4
	.globl	f
	.type	f, @function
f:
.LFB11:
	.cfi_startproc
	movl	%edi, %eax
	negl	%eax
	cmovs	%edi, %eax
	ret
	.cfi_endproc
.LFE11:
	.size	f, .-f  
	.p2align 4
	.globl	g
	.type	g, @function
g:
.LFB14:
	.cfi_startproc
	movl	%edi, %eax
	negl	%eax
	cmovs	%edi, %eax
	ret
	.cfi_endproc
.LFE14:
	.size	g, .-g
	.ident	"GCC: (Debian 12.2.0-14) 12.2.0"
	.section	.note.GNU-stack,"",@progbits