Tree Traversal

1
Tree Traversal
2
Traversal Algorithms

• preorder
• inorder
• postorder

3
PreOrder Traversal
4
Inorder Traversal
5
Postorder Traversal
6
In which order does a inorder traversal visit the
vertices in this ordered rooted tree?
procedure inorder(T ordered rooted tree) r
root of T if r is a leaf then list r else begin
l first child of r from left to right
T(l) subtree with l as its root
inorder(T(l)) list r for each child c of
r except for l left to right T(c)
subtree with c as its root
preorder(T(c)) end
output j e n k o p b f a c l g m d h i
7
In which order does a postorder traversal visit
the vertices in this ordered rooted tree?
8
Infix, Prefix, and Postfix Notation
represent complicated expressions using an
ordered rooted tree (typically binary)

• Algebraic expressions
• preorder Polish notation
• inorder infix notation
• postorder reverse Polish notation