Quicksort

var m, M, p, n, t;
m = argument0;
M = argument1;

if m >= M
 {
  return 0;
 }
if (m+1 == M)
 {
  if array[m] > array[M]
   {
    t = array[m];
    array[m] = array[M];
    array[M] = t;
   }
  return 0;
 }

n = (m+M) div 2;
p = array[n];
array[n] = array[M];
array[M] = p;

repeat M-m
 {
  if (array[m] > p) break;
  m += 1;
 }
repeat M-m
 {
  if (array[M] < p) break;
  M -= 1;
 }

while (m < M)
 {
  t = array[m];
  array[m] = array[M];
  array[M] = t;
  repeat M-m
   {
    if (array[m] > p) break;
    m += 1;
   }
  repeat M-m
   {
    if (array[M] < p) break;
    M -= 1;
   }
 }

array[argument1] = array[m];
array[m] = p;

quicksort(argument0, m-1);
quicksort(m+1, argument1);