Interview question on operator precedence #python3 #pythonforbeginners

In Python, operator precedence and associativity are important concepts that determine the order in which operators are evaluated in expressions.

**Operator Precedence:**

Operator precedence defines the priority of operators in an expression. Operators with higher precedence are evaluated first. For example, in the expression `2 + 3 * 4`, multiplication (`*`) has higher precedence than addition (`+`), so `3 * 4` is evaluated first, resulting in `2 + 12`.

Common operator precedence (from highest to lowest) in Python includes:

1. Parentheses `()`
2. Exponentiation `**`
3. Multiplication `*`, Division `/`, Floor Division `//`, Modulus `%`
4. Addition `+`, Subtraction `-`
5. Comparison Operators
6. Logical NOT `not`
7. Logical AND `and`
8. Logical OR `or`
9. Conditional Expression (Ternary) `if`-`else`
10. Assignment Operators (`=`, `+=`, `-=`, `*=`, `/=`, `//=`, `%=`, `**=`)

**Associativity:**

Associativity determines the order of evaluation when multiple operators with the same precedence appear in an expression. Most operators in Python have left-to-right associativity, meaning they are evaluated from left to right. For example, in the expression `a + b - c`, both addition (`+`) and subtraction (`-`) have the same precedence and left-to-right associativity, so the addition is evaluated first, followed by subtraction.

It's important to note that not all operators have left-to-right associativity. An example of right-to-left associativity is the exponentiation operator (`**`), where `2 ** 3 ** 2` is evaluated as `2 ** (3 ** 2)`.

Understanding operator precedence and associativity helps in writing expressions that produce the expected results without the need for excessive parentheses. It's crucial for reading and writing clear, concise, and accurate Python code.