Factorial is a positive number is the product of all number less than or equal to the positive number.
For example:
0! = 1
1! = 1
2! = 2 * 1! = 2
3! = 3 * 2! = 6
…
n! = n * (n – 1)!
Here is the sample code to calculate Factorial using both loop and recursion using c#.
///
///
class Program
{
static void Main(string[] args)
{
int number = 0;
Console.WriteLine(“Enter an integer number to calculate factorial: “);
Int32.TryParse(Console.ReadLine(), out number);
Console.WriteLine(“Factorial of ” + number + ” is: ” + CalculateFactoial(number));
Console.WriteLine(“Factorial of ” + number + ” is: ” + Factorial(number));
Console.ReadLine();
}
//Calculate factorial using loop
private static int CalculateFactoial(int number)
{
int factorial = 1;
for (int counter = 1; counter <= number; counter++)
{
factorial = factorial * counter;
}
return factorial;
}
//Calculate factorial using recursion
private static int Factorial(int number)
{
if (number == 0)
return 1;
else
return number * Factorial(number – 1);
}
}
[/csharp]
