Fibonacci Numbers

Statement

Fibonacci numbers are a sequence of numbers where each number is the sum of the two preceding numbers. Your task is to find the $n^{th}$ Fibonacci number.

The Fibonacci sequence is defined as:

$F_0 = 0,\space F_1 = 1,\space F_n = F_{n-1} + F_{n-2},\space$ for $n$ $\geq$ 2

Let’s say you have to find the fifth Fibonacci number in the sequence. From the sequence defined above, we know that $F_0 = 0$ and $F_1 = 1$. So, the sequence will be:

$0, 1, 1, 2, 3, 5$

Now, the fifth term will be 5.

Constraints:

• $0 \leq$ n $\leq 90$

Examples