# Postfix Expression from Expression Tree

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Expression Tree is used to represent expressions. Let us look at how to traverse an expression tree to produce an postfix expression from expression tree:

## Steps to Traverse Expression Tree to produce Postfix Expression for a*b+c

## Generate Postfix Expression From Expression Tree

Let us how to generate the Postfix expression from tree. A postfix expression is generated from the tree as follows:

__First consider the left subtree__**a * b**.- For
**a * b**, consider the left subtree**a**. Left subtree has only one node**a**, Hence, first write the same.Postfix expression created so far = a

- Consider the right subtree. Right subtree
**b**is just a node.Postfix expression created so far = a b

- Consider the root of subtree
*****.Postfix expression created so far = a b *

- For
__Consider the right subtree__Since the right subtree is just a simple node, there is no more subtrees to be checked**c**.Postfix expression created so far = a b * c

__Consider the root__**+**.Postfix expression created so far = a b * c +

## Postfix expression

a b * c +

How to write Prefix Expression >>

How to write Infix Expression >>

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