Doc formating consistency between slice sort and sort_unstable, and big O notation consistency#77969

Merged

bors merged 2 commits intorust-lang:masterfrom ryan-scott-dev:bigo-notation-consistency

Oct 23, 2020

+18-18

Commits on Oct 15, 2020

Made slice sort documentation consistent between stable and unstable versions
ryan-scott-dev
committed
Following rust-lang#74010 by converting some newer cases of backticked O notations to be italicized
ryan-scott-dev
committed