Sum of digits of a number
Detailed guide and Python implementation for the 'Sum of digits of a number' problem.
Problem Statement
Write a function sum_of_digits(n) that takes a non-negative integer n and returns the sum of its digits. For example, the digits of 123 are 1, 2, and 3, and their sum is 6.
- •0 <= n <= 10^9
Examples
n = 123
6
1 + 2 + 3 = 6.
n = 9999
36
9 + 9 + 9 + 9 = 36.
n = 0
0
The only digit is 0, so the sum is 0.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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