Answer to Question #272285 in C# for chi

Question

Write a program to calculate the factorial value of the input number n! Use the incrementation formula ( i++ ) for your solution instead of decrementation formula (i-­‐-­‐).

Apply the three looping statements for your solutions:

Enter a no. 4 Factorial value is: 24 (The computation is: 1*2*3*4=24)

1st Solution – using for loop

2nd Solution – using while loop

3rd Solution-­‐ using do while loop

Answer 1

using System;
using System.Collections.Generic;


namespace App
{
    class Program
    {




        public static void Main()
        {




            Console.Write("Enter a no.: ");
            int n = int.Parse(Console.ReadLine());




            Console.WriteLine("Factorial value is (using - for loop): {0}", ComputeFactorialWithFor(n));
            Console.WriteLine("Factorial value is (using - while loop): {0}", ComputeFactorialWithWhile(n));
            Console.WriteLine("Factorial value is (using - do while loop): {0}", ComputeFactorialWithDoWhile(n));




            Console.ReadLine();
        }


        private static int ComputeFactorialWithDoWhile(int n)
        {
            int factorial = 1;
            int i = 1;
            do
            {
                factorial *= i;
            } while (++i <= n);
            return factorial;


        }


        private static int ComputeFactorialWithWhile(int n)
        {
            int factorial = 1;
            int i = 1;
            while (++i <= n)
            {
                factorial *= i;
            }
            return factorial;
        }


        private static int ComputeFactorialWithFor(int n)
        {
            int factorial = 1;
            for (int i = 1; i <= n; i++)
            {
                factorial *= i;
            }
            return factorial;
        }
    }
}