using System;

public class Material

{

    public string Name;

    public string UnitOfMeasure;

    public double PricePerUnit;

    public double Number;

    public Material( string name, string unitOfMeasure, double pricePerUnit)

    {

        Name = name;

        UnitOfMeasure = unitOfMeasure;

        PricePerUnit = pricePerUnit;

    }

}

​

​

public class Program

{

    public static void Main()

    {

        Material[] materials = new Material[]

        {

            new Material("Brick", "per brick", 0.5),

            new Material("Plaster", "square metre", 2),

            new Material("Timber", "metre", 7.8),

            new Material("Cement", "kg", 5),

        };

        string optionInputText;

        int optionInputIndex;

        double Quantity = 0;

        int numberOfMaterials;

        string requiredMaterial;

        bool noMaterialsValid = false;

        double materialQuantity;

        double MinimumVat = 0;

        double MaximumVat = 0;

        Console.WriteLine("How many different materials do you require?");

            string numberOfMaterialsInput = Console.ReadLine();

            numberOfMaterials= int.Parse(numberOfMaterialsInput);

​

​

 for(int i = 0; i < numberOfMaterials; i++)

 { 

     noMaterialsValid = false;

        while(noMaterialsValid == false)

        { 

            for(int j = 0; j < materials.Length; j++)

            {

                string materialDescription = "(" + j + ") " + materials[j].Name;

                Console.WriteLine(materialDescription);

            }

​

            Console.WriteLine("please select an option shown above");

            optionInputText = Console.ReadLine();

            optionInputIndex = int.Parse(optionInputText);

​

                if(optionInputIndex < 0 || optionInputIndex > materials.Length -1)

                {

                    Console.WriteLine("please enter a valid option");

                }

                else

                {

                    Material selectedMaterial = materials[optionInputIndex];

                    noMaterialsValid = true;

                }

        }

 }  

    }

}