Factorial using recursion
Detailed guide and Python implementation for the 'Factorial using recursion' problem.
Problem Statement
Write a function factorial(n) that computes the factorial of a non-negative integer n using recursion. The factorial of n (written as n!) is the product of all positive integers from 1 to n. By definition, 0! = 1. The function should return the factorial as an integer.
- •0 <= n <= 20
Examples
n = 5
120
5! = 5 * 4 * 3 * 2 * 1 = 120.
n = 0
1
0! is defined as 1.
n = 7
5040
7! = 7 * 6 * 5 * 4 * 3 * 2 * 1 = 5040.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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