Understanding Recursion in C++

What is Recursion?

Recursion occurs when a function calls itself to solve smaller instances of the same problem. It simplifies complex problems by breaking them down into smaller, manageable parts.

Example of Recursion:

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

Sample Answer:

Recursion is used in C++ to solve problems that can be broken down into smaller sub-problems with similar characteristics. By reducing the problem size at each recursive call, recursion efficiently solves complex problems.

Base Case and Recursive Case

1. Base Case: Prevents infinite recursion by defining when the recursion should stop.
2. Recursive Case: The condition where the function calls itself to solve a smaller problem.

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

::: note In recursion, the base case ensures the function stops calling itself, while the recursive case solves smaller instances progressively. For example, in Fibonacci, the base cases are fibonacci(0) and fibonacci(1), while the recursive case computes fibonacci(n-1) + fibonacci(n-2) :::