Which of the following code snippets returns the factorial of a
given number? (Hint: Factorial of 5 = 5! = 1 * 2 * 3 * 4 * 5 =
120)

Question

BlackTom AI · Accepted Answer

The prompt asks to identify which code snippet returns the factorial of a given number, with the hint that 5! = 120.

First, I note that the provided data includes two very similar code snippets, but there is no list of answer options to evaluate. Without explicit options to compare, I can only analyze the snippets as presented and discuss typical correctness criteria for a factorial function.

Common expectations for a correct factorial function include:
- A base case that terminates recursion when the input is 0 or 1, since 0! = 1 and 1! = 1.
- A recursive case that multiplies the current number by the factorial of the previous number (num * factorial(num - 1)).
- Proper handling of edge cases, such as non-positive inputs, depending on the specification (some definitions treat negative inputs as undefined).

Now, consider the two snippets shown:
- Both snippets define a function named factorial that takes a single parameter num.
- Each snippet uses a base case of if(num == 1) return 1, which is a valid base case for positive integers greater than 1. However, missing 0 as a base case means 0! would not be handled correctly (0! should be 1).
- The recursive step in both snippets is return num * factorial(num - 1), which correctly expresses the core recursive relation for factorial, provided the base case is reached.
- The indentation and formatting in the snippets appear inconsistent or irregular (for example, in the second snippet there are extra spaces and uneven alignment). In Python, indentation matters for code blocks, so such formatting could cause a syntax error even if the logic is correct.
- Additionally, neither snippet explicitly handles the case where num <= 0, which could lead to infinite recursion or unexpected results for non-positive inputs.

With these observations, the key issues to flag for correctness are:
- The base case should include num <= 1 (or explicitly handle 0) to ensure 0! and 1! both return 1.
- The function should be syntactically valid in Python (proper indentation, spacing) to actually run.
- It may be wise to guard against non-integer or negative inputs if the specification requires it.

Regarding the statement that there are no answer options provided: since the task typically requires choosing from given options, the absence of answer options means we cannot definitively select which snippet is correct in the multiple-choice sense. If you provide the intended options as a list, I can compare them explicitly and explain which one correctly computes the factorial and why others fail.

If we were to propose a correct Python version based on standard factorial definition, a robust snippet would look like:

def factorial(num):
    if num < 0:
        raise ValueError("factorial is not defined for negative numbers")
    if num == 0 or num == 1:
        return 1
    return num * factorial(num - 1)

This version handles 0!, uses a clear base case, and guards against negative inputs. It also preserves clean indentation, which is essential in Python.

Fal25_CS003C_74229 Ch. 5 Pre-Quiz (Remotely Proctored)

Which of the following code snippets returns the factorial of a given number? (Hint: Factorial of 5 = 5! = 1 * 2 * 3 * 4 * 5 = 120)

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