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Preamble, in sequence, after traversal
Traversing the binary tree is divided into three types: the preamble, in order, the sequence . Preorder traversal of which the most important.
Why that name? Is The root node named order.
Such as a full node on FIG normal, A: root, B: left node, C: the right node.
Preamble sequence is ABC (first root);
In the BAC sequence is a sequence (in the middle of the root node);
After the order is order BCA (final root).
For example the result of the binary tree traversal FIG.
Preorder traversal (most from the middle): ABCDEFGHK
Preorder (starting from the left): BDCAEHGKF
Postorder (starting from the bottom left-most): DCBHKGFEA
Prefix, infix, postfix expression
Expression expression prefix, infix expressions, postfix expression of all four operations for four arithmetic expression evaluation