Program output for loop

harish reddy

8y1.6kLearn iOS Programming

//Write a program in C# Sharp to display the sum of the series [ 1+x+x^2/2!+x^3/3!+....]

int x = int.Parse(Console.ReadLine());

int n = int.Parse(Console.ReadLine());

int sum = 1 + x;

int top;

for (int i = 2; i <= n; i++)

{

top = x ^ i;

sum = sum + top;

}

Console.WriteLine(sum);

Not able to proceed further. pls help. Also can we use X^i for powering a number?

My main doubt is how can i put factorial also in the above loop...

I see many answers in google for the above program. but not able to understand. can someone help with using the above code i did.

5 Replies

Know the answer? Post it — somebody with the same question will find it here.

Sourabh Somani8y ago
Accepted answer
Here is the link
https://dotnetfiddle.net/uunWQI

Here is with loop
//[ 1+x+x^2/2!+x^3/3!+....]
using System;

public class Program
{
    public static void Main()
    {
        Console.Write("Enter x:");
        int x = int.Parse(Console.ReadLine());
        Console.Write("Enter n:");
        int n = int.Parse(Console.ReadLine());
        double sum = 1 + x;
        for (int i = 2; i <= n; i++)
        {
            int fact=1;
            for(int j=1;j<=i;j++)
            {
                fact*=j;
            }
            //sum = sum + ((Math.Pow(x,i)))/factorial(i);
            sum = sum + ((Math.Pow(x,i)))/fact;
        }
        Console.WriteLine(sum);
    }
    /*public static int factorial(int number)
    {
        if(number==0)
        {
            return 1;
        }
        else
        {
            return number*factorial(number-1);
        }

    }*/
}
Now Please accept the answer
harish reddy8y ago
You can also calculate loop to get factorial . can you post this using the loop?
Sourabh Somani8y ago
you want to get the power of the number in C3 we get Power of any number using Math.Pow method.

Here Math is the class and Pow is Static Method in which we pass 2 arguments
Base and Power
like if I want to get 5^2 which is 25 we know in C# language we will write

Math.Pow(5,2)

Well you can create your own method to get power but for your requirement I will suggest use this.

Second we don't have any method to get factorial of the number so I have created a method to get factorial of the number ofcourse you have to create a method otherwise you can't get this

You can also calculate loop to get factorial but recusive function is the best approach..

Please accept my answer if you get your answer
harish reddy8y ago
Thanks Sourab,

Cant we do it with out using another method :
public static int factorial(int number)
{
if(number==0)
{
return 1;
}
else
{
return number*factorial(number-1);
}
}
}
I mean cant we include this in the first for loop and in the void method itself?

I am starting to learn c sharp , so not able to understand the above part of the program.
Also cant we do X^i or may be 2 power 3 or 3 power 4, with out using Math.pow(x,i).

Is this math.pow(x,i) mandatory to use any number to other number power in c sharp? or is this short cut method.thanks.
Sourabh Somani8y ago
According to your formula you can try following program
using System;



public class Program

{

    public static void Main()

    {

        Console.Write("Enter x:");

        int x = int.Parse(Console.ReadLine());

        Console.Write("Enter n:");

        int n = int.Parse(Console.ReadLine());

        double sum = 1 + x;

        for (int i = 2; i <= n; i++)

        {

            sum = sum + ((Math.Pow(x,i)))/factorial(i);

        }

        Console.WriteLine(sum);

    }

    public static int factorial(int number)

    {

        if(number==0)

        {

            return 1;

        }

        else

        {

            return number*factorial(number-1);

        }



    }

}