Postfix notation is an unambiguous way of writing an arithmetic expression without parenthesis. It is defined so that if (exp1) op (exp2) is a normal, fully parenthesized expression whose operation is op, the postfix version of this is (pexp1) (pexp2) op where pexp1 and pexp2 are the postfix version of the original expression. For example:

( ( 5 + 2 ) * ( 8 - 3 ) / 4) is 5 2 + 8 3 - * 4 /

Develop a non recursive program to evaluate an expression in postfix notation using stacks.

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