using System;

public class Program

{ string[,] items = new string[,] {{"Eggs","10"}, {"Bread","15"},{"noodlesl","20"},{"juice","30"},{"vegetables","200"};

string input;

int price=0;

int quantity;

int index;

​

do {

input = Console.ReadLine();

Console.WriteLine("Enter quantity: ");

index = Convert.ToInt32(input)+1;

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

price += quantity * Convert.ToInt32(items[index,1]);

​

}while(input != "S");

​

Console.WriteLine("Your total: "+price);

} 

​

     public float Calculate_GST(float org_cost,  

                                float N_price) 

    { 

        return (((N_price - org_cost) * 100)  

                / org_cost); 

    } 

    public static void Main ()  

    { 

        float org_cost = 100; 

        float N_price = 120; 

        Console.Write(" GST = " + Calculate_GST 

                        (org_cost, N_price) + "%"); 

    } 

​

​

​