1 start := 1000; 

     2 x := start;

     3 y := start;

     4 z := start;

     5 while 0 < x do {

     6  while 0 < y do {

     7   while 0 < z do { z := z - 1 };

     8   z := start;

     9   y := y - 1

    10  };     

    11  y := start;

    12  x := x - 1

    13 }

    14