What is the difference between recursion and tail recursion?

Can you explain the difference between recursion and tail recursion?

Sure! Recursion is when a function calls itself to solve a problem, while tail recursion is a specific type of recursion where the recursive call is the last operation in the function.

Why is tail recursion more efficient?

Tail recursion can be optimized by the compiler to avoid adding a new stack frame for each call, which reduces memory usage and prevents stack overflow.

Can you give me an example of each?

Of course! A simple recursive function to calculate factorial is:

def factorial(n):
    if n == 0:
        return 1
    return n * factorial(n - 1)

For tail recursion, it would look like this:

def tail_factorial(n, accumulator=1):
    if n == 0:
        return accumulator
    return tail_factorial(n - 1, n * accumulator)

Are there any languages that don't support tail recursion?

Yes, not all programming languages optimize tail recursion. For example, languages like Java and C do not guarantee tail call optimization, while languages like Scheme and some functional languages do.