Table of Contents

- 1 What happens if you call a recursive function without a base case?
- 2 Does a recursive function need a base case?
- 3 When a recursive function calls itself what must we make sure of?
- 4 What happens if a base case is not handled in a recursive method and the method is executed?
- 5 What is base case and recursive case in a recursive function?
- 6 When recursion is used to solve a problem why must the recursive module call itself to solve a smaller version of the original problem?
- 7 What are the basic requirements of a recursive function?
- 8 What is the difference between a base case and recursive step?

## What happens if you call a recursive function without a base case?

By definition, a recursive function without a base case keeps calling itself recursively forever and never returns.

**What happens to a recursive method with no base condition?**

If there is no base case in a recursive method, or if the base case is never reached, the stack would grow forever—at least in theory. In practice, the size of the stack is limited. If you exceed the limit, you get a StackOverflowError .

### Does a recursive function need a base case?

A proper recursive function must always have a base case: The base case is a way to return without making a recursive call. In other words, it is the mechanism that stops this process of ever more recursive calls and an ever growing stack of function calls waiting on the return of other function calls.

**Can problems without base case be solved using recursion?**

A recursive algorithm must have a base case. A recursive algorithm must change its state and move toward the base case.

#### When a recursive function calls itself what must we make sure of?

The call to fib(77) should take no more than a fraction of a second. The first solution we could try here is the recursive one. Fibonacci numbers are recursive by definition: function fib(n) { return n <= 1?

**When a recursive function directly calls itself this is known as direct recursion?**

If a function calls itself, it’s known as direct recursion. This results in a one-step recursive call: the function makes a recursive call inside its own function body.

## What happens if a base case is not handled in a recursive method and the method is executed?

What happens if a base case is not handled in a recursive method and the method is executed? The program will eventually crash. Recursive methods are more efficient than iterative methods.

**Can recursive methods be void?**

Recursion will still work if there is a void function too. Every function will do its work and call the next recursive function and when the base condition is met the recursive call stack will start emptying as they have nothing to do now. The call stack will get emptied. Hope you got it !

### What is base case and recursive case in a recursive function?

Base case: the case in a recursive definition in which the solution is obtained directly. Directly recursive method: a method that calls itself. General case (Recursive case): the case in a recursive definition in which the method is calling itself.

**Can a recursive function have multiple base cases?**

A recursive implementation may have more than one base case, or more than one recursive step. For example, the Fibonacci function has two base cases, n=0 and n=1.

#### When recursion is used to solve a problem why must the recursive module call itself to solve a smaller version of the original problem?

When recursion is used to solve a problem, why must the recursive function call itself to solve a smaller version of the original problem? By reducing the problem with each recursive call, the base case will eventually be reached and the recursion will stop.

**What problems can be solved using recursion?**

Problems like finding Factorial of a number, Nth Fibonacci number and Length of a string can be solved using recursion.

## What are the basic requirements of a recursive function?

One critical requirement of recursive functions is the termination point or base case. Every recursive program must have a base case to make sure that the function will terminate. Missing base case results in unexpected behavior. Most of us are aware of at least two different ways of writing recursive programs.

**Why do recursive functions only have two condition checks?**

Since there are usually only two main conditions in a recursive function ( 1 – base case met, 2 – base case not met) it is only logical to only have two condition checks. The if checks for the base case, if the base case has not been reached else does calculations and sends the new recursive call.

### What is the difference between a base case and recursive step?

In a base case, we compute the result immediately given the inputs to the function call. In a recursive step, we compute the result with the help of one or more recursive callsto this same function, but with the inputs somehow reduced in size or complexity, closer to a base case. Consider writing a function to compute factorial.

**How do you know if recursion is finite?**

If every recursive step shrinks the problem, and the base case lies at the bottom, then the recursion is guaranteed to be finite. A recursive implementation may have more than one base case, or more than one recursive step. For example, the Fibonacci function has two base cases, n=0 and n=1. Recursive methods have a base case and a recursive step.