In this post I wrote a program in c# to calculate a factoral of Integer number using Recursive function and while loop also.
A Recursive usuallly, has the two specifications:
In the above article I try to explain how to calculate Factorial using Recursive function, while loop and for loop. So I hope its useful to you. Please post your feedback, question, or comments about this article.
What is Recursive Function:-
A Method can call another methods but it can also call itself. When a mathod calls itself, it'll be named recursive method.A Recursive usuallly, has the two specifications:
- Recursive method calls itself so many times until being satisfied.
- Recursive method has parameter(s) and calls itself with new parameter values.
Source code using Recursive function :-
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleDemoApp
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Enter a
integer number");
int number = Convert.ToInt32(Console.ReadLine());
if (number <= 0)
{
Console.WriteLine("Please enter
a positive integer number!");
Console.ReadKey();
return;
}
long fact = GetFactorial(number);
Console.WriteLine("{0}
factorial is {1}", number, fact);
Console.ReadKey();
}
// get
factorial of integer
private static long GetFactorial(int number)
{
if (number == 0)
{
return 1;
}
return number * GetFactorial(number-1);
}
}
}
Output:-
Source code using While Loop :-
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleDemoApp
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Enter a
integer number");
int number = Convert.ToInt32(Console.ReadLine());
if (number <= 0)
{
Console.WriteLine("Please enter
a positive integer number!");
Console.ReadKey();
return;
}
long fact = Factorial(number);
Console.WriteLine("{0}
factorial is {1}", number, fact);
Console.ReadKey();
}
// get
factorial of integer using while loop
static long Factorial(int input)
{
int answer = 0, count = 0;
if (input > 0)
{
count = 1;
while (count <= input)
{
if (count == 1)
{
answer = 1;
count++;
}
else
{
answer = count *
answer;
count++;
}
}
}
return answer;
}
}
}
Output:-
Source code using For Loop :-
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace factorial
{
class Program
{
static void Main(string[] args)
{
int i, number, fact;
Console.WriteLine("Enter the
Number");
number = int.Parse(Console.ReadLine());
if (number<0)
{
Console.WriteLine("Please enter
a positive interger value");
Console.ReadKey();
return;
}
if (number == 0)
{
Console.WriteLine("\nFactorial
of Given Number is: 1");
Console.ReadLine();
return;
}
fact = number;
for (i = number - 1; i >= 1; i--)
{
fact = fact * i;
}
Console.WriteLine("\nFactorial
of Given Number is: " + fact);
Console.ReadLine();
}
}
}
Output:-
In the above article I try to explain how to calculate Factorial using Recursive function, while loop and for loop. So I hope its useful to you. Please post your feedback, question, or comments about this article.
