Fibonacci Checker

Function Name: isFibonacciNumber

Description

Write a function named `isFibonacciNumber` that determines if a given non-negative integer number is a Fibonacci number. The Fibonacci sequence is a series of numbers where each number is the sum of the two preceding ones, usually starting with 0 and 1. That is, fib(0) = 0, fib(1) = 1, fib(2) = 1, fib(3) = 2, fib(4) = 3, fib(5) = 5, fib(6) = 8, and so on.

Your function should take one integer parameter and return a boolean value indicating whether the number is part of the Fibonacci sequence.

Requirements

• The function must take exactly one parameter: a non-negative integer.
• If the input number is a Fibonacci number, the function should return true; otherwise, it should return false.
• The solution should run efficiently and handle large input values with reasonable performance.
• Do not use recursion to solve this problem; an iterative or mathematical approach is expected.

Examples

If the input number is 8, the function should return true because 8 is a Fibonacci number (0, 1, 1, 2, 3, 5, 8).If the input number is 20, the function should return false because 20 is not a Fibonacci number.

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