back up next

quicksort.m


qsort [] = []
qsort (a:x) = qsort [b|b<-x;b<=a]
                  ++ [a] ++ 
              qsort[b|b<-x;b>a]

testdata = f 10
f n = concat(transpose [[0,2..2*n],[2*n-1,2*n-3..1]])

This is a functional version of quicksort, to see it work, say:

      qsort testdata
The reason we have to call the function `qsort' rather than `sort' is because there is a `sort' already defined in the standard environment. Note that the sort included in the standard environment is merge-sort.

Miranda home