Java Recursion Explained

A recursive algorithm refers to an algorithm that uses the function itself in its definition. In Java, recursive algorithms can be used to solve various problems such as calculating factorials, Fibonacci sequences, and more.

Here is an example of a recursive algorithm to calculate the factorial.

public class Main {
    public static void main(String[] args) {
        int n = 5;
        int result = factorial(n);
        System.out.println("Factorial of " + n + " is " + result);
    }

    public static int factorial(int n) {
        if (n == 0) {
            return 1;
        } else {
            return n * factorial(n - 1);
        }
    }
}

In this example, we have defined a factorial method to calculate the factorial of a given number. If the parameter n passed is 0, it returns 1; otherwise, it returns the result of n multiplied by factorial(n-1).

By recursively calling the factorial method, the problem can be broken down into smaller sub-problems until reaching the base case, then solving the sub-problems step by step to eventually obtain the final result.

It is important to note that when using recursive algorithms, ensure that the recursion eventually converges to the base case to avoid infinite recursion leading to stack overflow.