Can you explain recursion in C++ with examples?

Can you explain recursion in C++ with examples?

Sure! Recursion is a programming technique where a function calls itself to solve a problem. For example, a simple recursive function to calculate the factorial of a number is:

int factorial(int n) {
    if (n <= 1) return 1;
    return n * factorial(n - 1);
}

This function calls itself with a decremented value until it reaches the base case.

What is the base case in recursion?

The base case is a condition that stops the recursion. In the factorial example, the base case is when n is less than or equal to 1. This prevents infinite recursion and allows the function to return a value.

Can you give me another example of recursion?

Absolutely! Another common example is the Fibonacci sequence. Here's a recursive function to calculate the nth Fibonacci number:

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

This function calls itself twice for each value of n greater than 1.

What are the drawbacks of using recursion?

Some drawbacks include increased memory usage due to function call stack and potential stack overflow for deep recursion. Iterative solutions can sometimes be more efficient.