## Problem:

The fibonacci sequence is a famous bit of mathematics, and it happens to have a recursive definition. The first two values in the sequence are 0 and 1 (essentially 2 base cases). Each subsequent value is the sum of the previous two values, so the whole sequence is: 0, 1, 1, 2, 3, 5, 8, 13, 21 and so on. Define a recursive fibonacci(n) method that returns the nth fibonacci number, with n=0 representing the start of the sequence.

fibonacci(0) → 0
fibonacci(1) → 1
fibonacci(2) → 1

## Solution:

public int fibonacci(int n) {
if (n == 0) return 0;
else if (n == 1) return 1;
return fibonacci(n-1) + fibonacci(n-2);
}

1. public int fibonacci(int n) {
return (n ==0|| n == 1)? n : fibonacci(n-1) + fibonacci(n-2);
}

2. slightly simplified..

public int fibonacci(int n) {
if (n <= 1) {
return n;
}
return fibonacci(n - 2) + fibonacci(n - 1);
}

3. public int bunnyEars2(int bunnies) {
if(bunnies == 0) {
return 0;
}

int num = 2;
if(bunnies % 2 == 0) {
num = 3;
}

return num + bunnyEars2(bunnies - 1);
}