SIMSCRIPT II.5 Programming Language

Programming Language Concepts
normally mode is integer
define NOD and NODE as 1-dimensional arrays
reserve NODE(*) as 2
let TREE = NODE(*)
let NODE(*) = 0
reserve NODE(*) as 2
let NOD(*) = TREE
let NOD(1) = NODE(*)
let NODE(*) = 0
reserve NODE(*) as 2
let NOD(2) = NODE(*)
let NODE(*) = 0
:
end
NOD is used as a dummy array name to which a previous NODE pointer is assigned to allow nodes to
connect to the nodes above them in the tree. This is not the most efficient way to process such trees.
The tree constructed by the program above is illustrated in figure 2-6.
TREE
NODE(1) NODE(2)
NODE(1) NODE(2) NODE(1) NODE(2)
et cetera et cetera et cetera et cetera
Figure 2-6. Tree Construction
A recursive routine to destroy such a tree is shown below. Given the pointer to the root of the tree,
the routine follows all paths in the tree and destroys the nodes on them:
routine DESTROY(NODE)
normally mode is integer
define NODE as a 1-dimensional array
if NODE(*) is not zero,
for BRANCH = 1 to 2
call DESTROY(NODE(BRANCH))
release NODE(*)
always
return
end
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