# I want to ask question about the recursion lecture

Hello thanks for the lecture.

Are we getting the total of each recursion at the end of the process?

Cheers!

Hey,

Thank you for your question!

I am not sure if I completely understand it, but let me answer in the following way.

Let's consider the example with the sum of the first **n** Fibonacci numbers, let's for instance set **n = 3**. To return the sum of the first 3 Fibonacci numbers, you'd call the function **fib_2(3)**.

**Phase 1:**

Entering the **fib_2(3)** function, you would do the following:

1. check whether n = 0, which it is not;

2. check whether n = 1, which it is not;

3. call the functions **fib_2(2)** and **fib_2(1)**.

**Phase 1.1:**

Let's enter the function **fib_2(2)** which is part of the output from Phase 1. You would do the following:

1. check whether n = 0, which it is not;

2. check whether n = 1, which it is not;

3. call the functions **fib_2(1)** and **fib_2(0)**.

**Phase 1.1.1**:

Let's enter the function **fib_2(1)** which is part of the output from Phase 1.1. You would do the following:

1. check whether n = 0, which it is not;

2. check whether n = 1, which it, so this function would return a 1;

**Phase 1.1.2**:

Let's enter the function **fib_2(0)** which is part of the output from Phase 1.1. You would do the following:

1. check whether n = 0, which it is, so this function would return a 0;

Therefore, the result of the function **fib_2(2)** from Phase 1.1 is 1 + 0 = 1.

**Phase 1.2:**

Let's enter the function **fib_2(1)** which is part of the output from Phase 1. You would do the following:

1. check whether n = 0, which it is not;

2. check whether n = 1, which it is, so this function would return a 1;

Therefore, the result of the function **fib_2(3)** from Phase 1 is **fib_2(2)** + **fib_2(1)** = 1 + 1 = 2.

I hope my notation makes sense to you and that I also managed to answer your question :)

Kind regards,

365 Hristina