Infix, Postfix, and Prefix notations are three different but equivalent ways of writing expressions.
Postfix, also known as Reverse Polish Notation (RPN), and Prefix, known as Polish Notation, are alternative formats.
- Infix: Operators are placed between operands. Example:
A + B - Postfix: Operators come after operands. Example:
AB+ - Prefix: Operators precede operands. Example:
+AB
Here are additional examples:
| Infix | Postfix | Prefix | Notes |
|---|---|---|---|
| A * B + C / D | A B * C D / + | + * A B / C D | Multiply A and B, divide C by D, then add the results. |
| A * (B + C) / D | A B C + * D / | / * A + B C D | Add B and C, multiply by A, then divide by D. |
| A * (B + C / D) | A B C D / + * | * A + B / C D | Divide C by D, add B, then multiply by A. |