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Quiz 2 - Infix / Postfix Expression

Infix / Postfix Expression

1. The following postfix expression with single-digit operands is evaluated using a stack:

8 2 3 ^ / 2 3 * + 5 1 * -

Note that ^ is the exponentiation operator. The top two elements of the stack after the first * is evaluated are:

Answer: 6, 1

2. Assume that the operators +, -, × are left-associative and ^ is right-associative. The order of precedence (from highest to lowest) is ^, x, +, -. The postfix expression corresponding to the infix expression a + b × c - d ^ e ^ f is

Answer: abc × + def ^ ^ -

3. The result evaluating the postfix expression 10 5 + 60 6 / * 8 – is

Answer: 142

4. Convert the following infix expression into its equivalent post fix expression (A + B^ D) / (E – F) + G

Answer: ABD^ + EF – / G+

5. The best data structure to check whether an arithmetic expression has balanced parenthesis is a __________

Answer: Stack

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