Sum of N natural numbers
Detailed guide and Python implementation for the 'Sum of N natural numbers' problem.
Problem Statement
Write a function sum_n_natural(n) that takes a non-negative integer n and returns the sum of the first n natural numbers using the formula n * (n + 1) / 2. If n is 0, return 0.
- •0 <= n <= 10^6
Examples
n = 6
21
Using the formula: 6 * 7 / 2 = 21.
n = 0
0
There are no natural numbers to sum, so the result is 0.
n = 100
5050
100 * 101 / 2 = 5050.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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