Prefix To Infix

Data Structures/Concepts Used:

Uses 3 Stacks,each for: (1)Input (2)Operators (3)Output

Description:

Please write a C++ source code/program that will convert an expression in infix notation ( e.g. 2 * 3 + (6 / 4) - 8 ) to the equivalent expression in prefix (polish) notation (e.g. - + * 2 3 / 6 4 8 ).

###Algorithm for Converting infix to prefix Pushes the contents of the string into the input stack
While the input stack is not empty...

• If it is operand, add it to output string.
• If it is Closing parenthesis, push it on stack.
• If it is an operator, then
  • If stack is empty, push operator on operator stack.
  • If the top of stack is closing parenthesis, push operator on stack.
  • If it has same or higher priority than the top of stack, push operator on stack.
  • Else pop the operator from the stack and add it to output string, repeat step 5.
• If it is a opening parenthesis, pop operators from stack and add them to output string
  until a closing parenthesis is encountered. Pop and discard the closing parenthesis.
• If there is no more input, unstack the remaining operators and add them to output string.

Output:

-Infix to Prefix Converter-

Please enter a Mathematical Expression
(2*3+(6/4)-8)
-+*23/648
Would  you like to convert another expression? (y/n)y

Please enter a Mathematical Expression
2*3/(2-1)+5*(4-1)
+/*23-21*5-41
Would  you like to convert another expression? (y/n)n



() Code by Tacuma Solomon
() Not for Redistribution or Reuse.

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