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-The inner, non-leaf nodes of the
-tree do have associated values. But what values they are can be determined from
-the structure of the tree and the values of the node's left and right children.
-So the inner node doesn't need its own independent label.
+The inner, non-leaf nodes of the tree may have associated values. But if so,
+what values they are will be determinable from the structure of the tree and the
+values of the node's left and right children. So the inner nodes don't need
+their own independent labels.
In another sort of tree, the tree's inner nodes are also labeled: