What is the optimal time complexity of solving Find the Nth Term of the Fibonacci Series?

The optimized solution achieves a time complexity of O(n) by using sorting, mathematical shortcuts, or hash table lookups.

What is the auxiliary space complexity for Find the Nth Term of the Fibonacci Series?

The space complexity is O(1) since we only use a minimal/constant amount of extra memory for tracking variables (or auxiliary space if dynamic structures are allocated).

What are the typical edge cases we must handle in Find the Nth Term of the Fibonacci Series?

Key edge cases include empty collections, negative or large bounds causing integer overflow, arrays with only one element, or inputs where target criteria are not met.

How can we optimize the brute force approach for Find the Nth Term of the Fibonacci Series?

Brute force methods often inspect all possible combinations. We optimize this by sorting the input list to enable binary search, or tracking processed items in a set to avoid redundant nested loop lookups.

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Find the Nth Term of the Fibonacci Series

Learn how to solve the 'Find the Nth Term of the Fibonacci Series' problem. This detailed resource details brute force and optimized approaches.

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Problem Statement

Easy

Write a function fibonacci_nth(n) that takes a positive integer n and returns the nth term of the Fibonacci series (1-indexed). The series is: F(1) = 0, F(2) = 1, F(3) = 1, F(4) = 2, F(5) = 3, ...

Constraints

•1 <= n <= 50

Examples

Example 1

Input

n = 5

Output

Explanation

The 5th Fibonacci term is 3. The series: 0, 1, 1, 2, 3.

Example 2

Input

n = 1

Output

Explanation

The 1st Fibonacci term is 0.

Example 3

Input

n = 10

Output

Explanation

The 10th Fibonacci term is 34. The series: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34.

Need a Hint?

Use simple arithmetic operators (like modulo `%`, division `//`), conditional checks, or loops to inspect number properties.

Edge Cases to Watch

Empty list or null input variables
Single item lists/arrays
Extremely large input bounds causing integer or stack overflow

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