Factorial of a number
Detailed guide and Python implementation for the 'Factorial of a number' problem.
Problem Statement
Write a function factorial(n) that takes a non-negative integer n and returns its factorial. The factorial of n (written as n!) is the product 1 × 2 × 3 × ... × n. By definition, 0! = 1.
- •0 <= n <= 20
Examples
n = 5
120
5! = 1 × 2 × 3 × 4 × 5 = 120.
n = 0
1
0! is defined as 1.
n = 10
3628800
10! = 3628800.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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