1. Converting Infix to Prefix Infix, Postfix and Prefix notations are three different but equivalent ways of writing expressions. In Infix notations, operators are written in-between their operands. However, in Prefix expressions, the operator comes before the operands. Assume the infix expression is a string of tokens delimited by spaces. The operator tokens are *, /, +, and -, along with the left and right parentheses, ( and ). The operand tokens are the single-character identifiers A, B, C, and so on. The following steps will produce a string of tokens in prefix order: 1. Reverse the infix expression i.e A + B * C will become C * B + A. Note while reversing each "(' will become ' and each ) becomes '('. 2. Obtain the postfix expression of the modified expression I.e CB * A +, 3. Reverse the postfix expression. Hence in our example prefix is + A * B C.

1. Converting Infix to Prefix Infix, Postfix and Prefix notations are three different but equivalent ways of writing expressions. In Infix notations, operators are written in-between their operands. However, in Prefix expressions, the operator comes before the operands. Assume the infix expression is a string of tokens delimited by spaces. The operator tokens are , /, +, and -, along with the left and right parentheses, ( and ). The operand tokens are the single-character identifiers A, B, C, and so on. The following steps will produce a string of tokens in prefix order: 1. Reverse the infix expression i.e A + B C will become C * B + A. Note while reversing each "(' will become ' and each ) becomes '('. 2. Obtain the postfix expression of the modified expression I.e CB * A +, 3. Reverse the postfix expression. Hence in our example prefix is + A * B C.

C++ Programming: From Problem Analysis to Program Design

8th Edition

ISBN:9781337102087

Author:D. S. Malik

Publisher:D. S. Malik

Chapter2: Basic Elements Of C++

Section: Chapter Questions

Problem 4PE: 4. Repeat Programming Exercise 3 by declaring numl, num2, and num3, and average of type double....

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