C# method calling

Question

I'm starting out in C# and coding in general.

I've made an attempt in coding a console based trinomial calculator, however I'm having trouble with the parameters of last two methods in the main method (Calculate and DisplayResult). Visual studio keeps saying:

there is no argument given that corresponds to the required formal parameter.

Can anyone help me?

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace TrinomialCalculator
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Trinomial Calculator");
            Console.WriteLine("====================");
            Console.ReadLine();
            Console.Clear();
            GetValues();
            Calculate();
            DisplayResult();
        }
        static int[] GetValues()
        {
            int[] values = new int[3];
            string numInput;
            Console.WriteLine("ax^2+bx+c");
            Console.WriteLine("=========");
            Console.ReadLine();

            while (true)
            {
                Console.WriteLine("Enter an integer for 'a': ");
                numInput = Console.ReadLine();
                int.TryParse(numInput, out values[0]);
                Console.WriteLine("Enter an integer for 'b': ");
                numInput = Console.ReadLine();
                int.TryParse(numInput, out values[1]);
                Console.WriteLine("Enter an integer for 'c': ");
                numInput = Console.ReadLine();
                int.TryParse(numInput, out values[2]);

                if (values[0] == 0 || values[1] == 0 || values[2] == 0)
                {
                    Console.WriteLine("One or more inputs are invalid. Try again.");
                    Console.ReadLine();
                    Console.Clear();
                    continue;
                }
                else
                {
                    break;
                }
            }
            Console.WriteLine("{0}x^2+{1}x+{2}", values[0], values[1], values[2]);
            Console.ReadLine(); 
            Calculate(values);
            return values;
        }
        public static double[] Calculate(int[] values)
        {
            double[] result = new double[2];
            result[0] = -values[1] + Math.Sqrt(values[1] ^ 2 - 4 * values[0] * values[2]);
            result[1] = -values[1] - Math.Sqrt(values[1] ^ 2 - 4 * values[0] * values[2]);
            DisplayResult(result);
            return result;
        }
        static void DisplayResult(double[] result)
        {
            Console.WriteLine("X(1)={0}\n X(2)={1}", result[0], result[1]);
            Console.ReadKey();
        }
    }
}

Answer 1

The method Calculate and DisplayResult have 1 parameters but they invoked with 0 arguments.

Change your code like this:

static void Main(string[] args)
{
    Console.WriteLine("Trinomial Calculator");
    Console.WriteLine("====================");
    Console.ReadLine();
    Console.Clear();
    double[] x =  Calculate(GetValues());
    DisplayResult(x);
}

Answer 2

You are not passing the parameters to the methods. There are also things in the code that aren't needed, like the while(true) loop and else clauses that don't do anything.

I rewrote this a little. Compare to yours and see what you think.

Good luck learning programming. It is a great profession.

using System;

namespace TrinomialCalculator
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Trinomial Calculator");
            Console.WriteLine("====================");
            GetValues();
            Console.ReadLine();
        }
        static void GetValues()
        {
            Console.WriteLine("ax^2+bx+c");
            Console.WriteLine("=========");

            string numInput;
            int[] values = new int[3];

            Console.WriteLine("Enter an integer for 'a': ");
            numInput = Console.ReadLine();
            int.TryParse(numInput, out values[0]);
            Console.WriteLine("Enter an integer for 'b': ");
            numInput = Console.ReadLine();
            int.TryParse(numInput, out values[1]);
            Console.WriteLine("Enter an integer for 'c': ");
            numInput = Console.ReadLine();
            int.TryParse(numInput, out values[2]);

            if (values[0] == 0 || values[1] == 0 || values[2] == 0)
            {
                Console.WriteLine("One or more inputs are invalid. Try again.");
                return;
            }

            Console.WriteLine("{0}x^2+{1}x+{2}", values[0], values[1], values[2]);
            DisplayResult(values);
        }
        static double[] DisplayResult(int[] values)
        {
            double[] result = new double[2];
            result[0] = -values[1] + Math.Sqrt(values[1] ^ 2 - 4 * values[0] * values[2]);
            result[1] = -values[1] - Math.Sqrt(values[1] ^ 2 - 4 * values[0] * values[2]);
            Console.WriteLine("X(1)={0}\n X(2)={1}", result[0], result[1]);
            return result;
        }
    }
}