Question

python in this assignment you will a stack to convert prefix expressions directly to postfix expressions. you may not use recursion as we will use recursion to revisit this problem in lab 2?

Answer 1

To convert prefix expressions to postfix using a stack, start from the rightmost character, pushing operands onto the stack and handling operators by popping two operands and concatenating them in a postfix manner. An example is provided.

Step-by-step explanation:

In this assignment, you will use a stack to convert prefix expressions directly to postfix expressions using Python. Recursion should not be used in this assignment, as it will be revisited in Lab 2. To convert a prefix expression to postfix, you can follow these steps:

1. Start from the rightmost character in the prefix expression.
2. If the character is an operand, push it onto the stack.
3. If the character is an operator, pop two operands from the stack, concatenate them in a postfix manner, and push the result back onto the stack.
4. Repeat steps 2-3 until all characters in the prefix expression have been processed.
5. The final result will be the postfix expression obtained from the top of the stack.

For example, let's convert the prefix expression '+AB' to postfix:

1. Start at 'B'.
2. 'B' is an operand, so push it onto the stack.
3. Move to 'A'.
4. 'A' is an operand, so push it onto the stack.
5. Finally, move to '+'.
6. '+' is an operator, so pop 'A' and 'B' from the stack, concatenate them in a postfix manner (AB+), and push the result ('AB+') back onto the stack.
7. The final result is 'AB+'.