1. Basic Sum

Grokking the Art of Recursion for Coding Interviews

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1. Basic Sum

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Problem Statement

Calculate the Sum of the First N Natural Numbers Using a Recursive Approach.

The sum of first N natural numbers is equal to N + (N-1) + (N-2) + ... + (3) + (2) + (1). The following table shows a sample input/output description table:

Input (s)	Output (s)	Explanation
N = 5	Sum = 15	The first 5 natural numbers are 1, 2, 3, 4, and 5. The sum of these numbers is 1 + 2 + 3 + 4 + 5 = 15.
N = 10	Sum = 55	The first 10 natural numbers are 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. The sum of these numbers is 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55.
N = 1	Sum = 1	The first natural number is 1. The sum of this number is 1.

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Table of Contents

Problem Statement

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