Recursion Factorial terminating due to StackOverfl

问题:

I am trying to learn recursion and I am attempting to do factorial's via recursion instead of loops, but my program is causing "Process is terminated due to StackOverflowException

class RecursionFactorial
{
    public static int n;

    static void Main(string[] args)
    {
        string input;

        Console.WriteLine("Please enter a number to work out the factorial");
        input = Console.ReadLine();
        bool test = int.TryParse(input, out n);
        fact(n);

    }
    public static int fact(int y)
    {
        int count = n;
        if (y <= 1)
        {
            Console.WriteLine(y);
        }
        else
        {
            count = (count * y);
            Console.WriteLine(count);
            fact(y - 1);
        }
    }
}

回答1:

In any Recursion you must have a case,where your recursion is ended.So you must enter return keyword to your function.

public static int fact(int y)
{
    if (y <= 1)
    {
        return 1;
    }
    else
    {
        return y * fact(y - 1);
    }
}

回答2:

fixed with this code:

        static void Main(string[] args)
    {
        int n;
        string input;

        Console.WriteLine("Please enter a number to work out the factorial");
        input = Console.ReadLine();
        bool test = int.TryParse(input, out n);

        int factorial = fact(n);
        Console.WriteLine("{0} factorial is {1}", n, factorial);
        Console.ReadLine();

    }
    public static int fact(int y)
    {
        if (y <= 1)
        {
            return 1;
        }
        else
        {
            return y * fact(y - 1);
        }