Postfix evaluation

Question

The following post-fix expression with single digit operands is evaluated using stack,
                     $16\;2\;4\;\wedge \; / \;4\;3\;*\;+\;6\;2\;*\;-$

Note that $\wedge$ is the exponential operator. What is the maximum height of the stack and the final value of post-fix evaluation respectively are

a. $3,\;1$         b. $4,\;1$        c. $3,\;12$        d. $2,\;1$

Comments

Yup! Its right Maximum stack size is 3 and top of the stack is 1.

Answer 1

16 2 4 ^

16 16 /

1 4 3 *

1 12 +

13 6 2 *

13 12 -

1

So, Ans will be max height of stack 3

and final value 1

Comments

Does we will not push operator onto the stack before computation? If we push maximum height should be 4. Please correct me if I am wrong

Answer 2

(P.S : Please bear with my poor handwriting :( )

Comments

vijaycs07 to calculate it we use operand stack . for every operator we do 2 pop with 1 push .

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max stack height will be 3.

Following steps are performed during postfix evaluation:-

1 Pop the operator from the operator stack.

2 Pop the value stack twice, getting two operands.

3 Apply the operator to the operands, in the correct order.

4 Push the result onto the value stack.

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shouldnt' the height be 4, as max 4 elements are present in the stack?