using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("By Brandon Eduardo Cortes Correa");

        Console.WriteLine("");

    int g1,cr,j;

    int ntrm;

    double sum=0,tn,gpn;

    Console.Write("\n\n");

    Console.Write("Find the Sum of GP series:\n");

    Console.Write("----------------------------");

    Console.Write("\n\n");  

​

​

    Console.Write("Input the first number of the G.P. series: ");

    g1 = Convert.ToInt32(Console.ReadLine());   

​

    Console.Write("Input the number or terms in the G.P. series: ");

    ntrm = Convert.ToInt32(Console.ReadLine()); 

​

    Console.Write("Input the common ratio of G.P. series: ");

    cr = Convert.ToInt32(Console.ReadLine());   

​

/*-------- generate G.P. series ---------------*/

     Console.Write("\nThe numbers for the G.P. series:\n ");

     Console.Write("1  ");

​

     for(j=1;j<=ntrm;j++)

       {

        gpn=Math.Pow(cr,j);

        Console.Write("{0}  ",gpn);

       }  

/*-------- End of G.P. series generate ---------------*/

​

​

    sum = (g1*(1 - (Math.Pow(cr,ntrm+1))))/(1-cr);

       tn = g1 * (Math.Pow(cr,ntrm-1));

​

    Console.Write("\nThe tn terms of G.P. : {0}\n\n",tn);

    Console.Write("\nThe Sum of the G.P. series : {0}\n\n",sum);

}

}