Today, we’ll solve the previous Fibonacci problem using the dreaded recursion approach. A little bit of theory was explored in this video, and today, I’ll straight to the point

Fibonacci Recursively in Theory

Just to remember:

• A recursive method is a method that calls itself.
• A recursive method usually solves a smallest version of the bigger (original) problem.

When it comes to Fibonacci, the definition already gives us a hint of how to solve it recursively:

To get the next number in a sequence, you have to sum the previous two numbers

Let’s say that we want the first 8 numbers in the Fibonacci sequence:

Plain Text

1

0 1 1 2 3 5 8 13

Notice that to get the value 13, we need to first calculate the first 7 numbers of a Fibonacci sequence. But to get the value 8, we need to first calculate the first 6 numbers of a Fibonacci sequence. And to get the value 5, we need to first calculate the first 5 numbers of a Fibonacci sequence.

Yup, you got it : ) We need to calculate the Fibonacci number of the previous 2 numbers

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