Revert "Delete Quicksort.hs"

This reverts commit d1b0347ed961f8759b04044b2cd1f8cc44fb08c4.
Revert "one file"

This reverts commit d4a658d2740ffc820f838ea7e0954c3c1419fc02.
Revert "one file"

This reverts commit dffd7386cad26f441f80ac99860f5739cd8d1078.