Q: 2. B) Trace the evaluation of the expression 4 8 + 6 5 -* 3 2 2 2, given the algorithm of postfix evaluation and fill the table. (10 pts)

EVALUATION OF POSTFIX EXPRESSION

Let P is an expression written in postfix notation.

1) STACK=empty stack.

2) Scan P from left to right and repeat step 3 and 4 for each symbol in P until end of expression.

3) If an operand is encountered, push it on STACK.

4) If an operator x encountered then;

a) Operand 2= pop (STACK).

b) Operand 1= pop (STACK).

c) Value= operand1 x operand 2.

d) Push value on STACK.

5) Return the value at top of the STACK.

6) Exit.

Number of symbol

Symbol Scan

Operand 1

Operand 2

Value

Stack

1

4

2

8

3

+

4

6

5

5

6

-

7

*

8

3

9

2

10

-

11

2

12

2