# Convert Infix to Prefix Expression

Objective: Given an Infix expression, write an algorithm to convert it into Prefix expression.

Example:

```Input: Infix expression - A + B
Output: Prefix expression- +AB

Input: Infix expression - A+B*(C^D-E)
Output: Prefix expression- +A*B-^CDE
```

Approach: Use Stack

• Operator stack: This stack will be used to keep operations (+, -, *, /, ^)

Order of precedence of operations

1. ^ (Exponential)
2. / *
3. + –

Note: brackets ( ) are used to override these rules.

Algorithm:

• Reverse the given infix expression. ( Note: do another reversal only for brackets).
• Do Infix to postfix expression and get the result.
• Reverse the result to get the final expression. (prefix expression) .

Please see the walkthrough of an example below for more understanding.

Complete Code:

Output:

```Infix Expression: A+B*(C^D-E)
Prefix Expression: +A*B-^CDE
```

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If you find anything incorrect or you feel that there is any better approach to solve the above problem, please write comment.
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