Recursive function in JavaScript

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Recursion is a programming concept that is applicable to all programming languages including JavaScript. 



What is a recursive function?
Recursive function is function that calls itself. 

When writing recursive functions there must be a definite break condition, otherwise we risk creating infinite loops.

Example : Computing the factorial of a number without recursion

function factorial(n)

{

    if (n == 0 || n == 1)

    {

        return 1;

    }

       

    var result = n;

    while (n > 1)

    {

        result = result * (n - 1)

        n = n - 1;

    }

    return result;

}

document.write(factorial(5));

Output : 120

Example : Computing the factorial of a number using a recursive function

function factorial(n) 
{
    if (n == 0 || n == 1) 
    {
        return 1;
    }
    return n * factorial(n - 1);
}

document.write(factorial(5));

Output : 120