Bubble Sort

This is a Bubble-Sortroutine
Captured from a messagein a public Internet news group (see Internet - Newsgroups)

 
/* ------------------------------------------------------------------ */
/* function: bubble sort routine                                      */
/*                                                                    */
/* call:     BubbleSort                                               */
/*                                                                    */
/* returns:  nothing                                                  */
/*                                                                    */
/* notes:    You must save the elements to sort in the stem "STEM."   */
/*           stem.0 must contain the number of elements in the stem.  */
/*                                                                    */
/*                                                                    */
BubbleSort: PROCEDURE expose stem.

  do i = stem.0 to 1 by -1 until flip_flop = 1
    flip_flop = 1
    do j = 2 to i
      m = j - 1
      if stem.m >> stem.j then                               /* v2.80 */
      do
        xchg   = stem.m
        stem.m = stem.j
        stem.j = xchg
        flip_flop = 0
      end /* if stem.m ... */
    end /* do j = 2 ... */
  end /* do i = stem.0 ... */
return