SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
This routine, when called by a statement such as call DESTROY(TREE), calls upon itself as each
node destroys the nodes below it. Because each node either points to a successor node or is zero,
the routine can tell whether it has to follow a downward path to destroy successor nodes, or whether
it can destroy the node it is working on by releasing it. Perhaps the easiest way to understand this
routine is to construct a typical tree, such as that shown in figure 2-7, and follow the logic through.
Figure 2-7. A Binary Tree
By changing one statement, as shown below, the routine can easily be expanded to destroy not only
binary trees, but those containing limitless branches as well:
routine DESTROY(NODE)
normally mode is integer
define NODE as a 1-dimensional array
if NODE(*) is not zero,
for BRANCH = 1 to dim.f(NODE(*))
call DESTROY(NODE(BRANCH))
release NODE(*)
always
return
end
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