Page 3 - DATA STRUCTURE-STACKS & QUEUES
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B) Algorithm – Evaluation of Postfix Expression
1. Let P be the expression in POSTFIX notation
2. Scan P from left to write and repeat steps 3 to 4 for each element of P
3. If (element = operand) Push it into Stack
4. If (element = operator)
i. POP first element from TOP and let it be A
ii. POP second element from TOP and let it be B
iii. Perform OPERATION B operator A
iv. PUSH result in STACK
5. POP the value from stack TOP which is result of the expression
Solve the following expression using Stack
5 4 6 + * 4 9 3 / + *
