Infix : An expression is called the Infix expression if the operator appears in between the operands in the expression. Simply of the form (operand1 operator operand2).
Example : (A+B) * (C-D)
Prefix : An expression is called the prefix expression if the operator appears in the expression before the operands. Simply of the form (operator operand1 operand2).
Example : *+AB-CD (Infix : (A+B) * (C-D) )
Given a Prefix expression, convert it into a Infix expression.
Computers usually does the computation in either prefix or postfix (usually postfix). But for humans, its easier to understand an Infix expression rather than a prefix. Hence conversion is need for human understanding.
Input : Prefix : *+AB-CD Output : Infix : ((A+B)*(C-D)) Input : Prefix : *-A/BC-/AKL Output : Infix : ((A-(B/C))*((A/K)-L))
Algorithm for Prefix to Infix:
- Read the Prefix expression in reverse order (from right to left)
- If the symbol is an operand, then push it onto the Stack
- If the symbol is an operator, then pop two operands from the Stack
Create a string by concatenating the two operands and the operator between them.
string = (operand1 + operator + operand2)
And push the resultant string back to Stack
- Repeat the above steps until end of Prefix expression.
Infix : ((A-(B/C))*((A/K)-L))
- Prefix to Postfix Conversion
- Postfix to Prefix Conversion
- Postfix to Infix
- Evaluation of Prefix Expressions
- Convert Infix To Prefix Notation
- Stack Data Structure (Introduction and Program)
- Design a stack that supports getMin() in O(1) time and O(1) extra space
- Iterative Tower of Hanoi
- Stack | Set 4 (Evaluation of Postfix Expression)
- Expression Evaluation
- Stack | Set 2 (Infix to Postfix)
- The Stock Span Problem
- Next Greater Element
- Reverse a stack using recursion
- Check for balanced parentheses in an expression
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