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Non Fibonacci Number
Easy Accuracy: 54.38% Submissions: 377 Points: 2

Given a positive integer N, your task is to print the Nth non Fibonacci number. The Fibonacci numbers are defined as:

Fib(0) = 0

Fib(1) = 1

for n >1, Fib(n) = Fib(n-1) + Fib(n-2)

Example 1:

Input: N = 5
Output: 10
Explaination: The first 5 non-fibonacci 
numbers are 4, 6, 7, 9, 10.

Example 2:

Input: N = 15
Output: 22
Explaination: The fibonacci numbers 
are 1, 2, 3, 5, 8, 13, 21, 34. Here 
22 becomes the 15th non-fibonacci 

Your Task:
You do not need to read input or print anything. Your task is to complete the function nonFibonacci() which takes the value N and returns the Nth non-fibonacci number.

Expected Time Complexity: O(N)
Expected Auxiliary Space: O(1)

1 ≤ N ≤ 105

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Non Fibonacci Number

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