using System;

 class Program

{

     public string U;

     public string name;

     public string id;

     Console.WriteLine( "Please input your ID No. Here : ");

     Console.ReadLine();

     public I(string U,string name,string id){

         this.U = U;

         this.name = name;

         this.id = id;

         return Iden;

                   }

​

    public static void Main()

    {

        string e;

        string n;

    const string co = "  BASIC CALCULATOR ";    

    Console.WriteLine(co);

    Console.WriteLine();    

    const string yn = "instructions are available, simply type in yes or no ";

    Console.WriteLine(yn);  

     Console.WriteLine();

    e=Console.ReadLine();

    if(e== "yes")

    {

    const string co1 = "INSTRUCTIONS:";

    Console.WriteLine(co1);

    Console.WriteLine();

    const string co2 = "A) FOR INCREMENTS: ";

    Console.WriteLine(co2);

    const string co3 = " for a prefix increment for the first input please type '++X' in the operator.";

    Console.WriteLine(co3);

    const string co4 = " for a postfix increment for the first input please type 'X++' in the operator.";

    Console.WriteLine(co4); 

    const string co5 = " for the prefix increment for the second input please type in '++Y' in the operator.";  

    Console.WriteLine(co5); 

    const string co6 = "for postfix increment on the second input please type in 'Y++' in the operator.";

    Console.WriteLine(co6); 

    Console.WriteLine();    

    const string co7 = "B) FOR DECREMENTS: ";

    Console.WriteLine(co7);

    const string co8= " for the prefix decrement for the first input please type '--X' in operators.";

    Console.WriteLine(co8);

    const string co9 = "for the postfix decrement for the first input please type 'X--' in operators.";

    Console.WriteLine(co9); 

    const string co10= " for the prefix decrement for the second input please type '--Y' in operators.";    

    Console.WriteLine(co10);

    const string co11 = "for the postfix decrement for the second input please type 'Y--' in operators.";   

    Console.WriteLine(co11);    

    Console.WriteLine();

    }

​

        string in1;

        string in2;

        string in3;

        int x;

        int y;

        int z;

    Console.WriteLine(" Please input your name : ");

    n=Console.ReadLine();   

   Console.WriteLine("Welcome " + n );

    Console.WriteLine();    

     Console.WriteLine("Please fill in the areas below: ");    

        Console.WriteLine();

    Console.WriteLine("enter first input:");

    in1=Console.ReadLine();

     x=Convert.ToInt32(in1);

    if(x >= 1)

    {

        Console.WriteLine();

    }

    Console.WriteLine("enter second input: ");

    in2=Console.ReadLine();

    y=Convert.ToInt32(in2);

   Console.WriteLine("operator: ");

    in3=Console.ReadLine(); 

while (in3 > 0){    

    if(y >= 1)

    {

        Console.WriteLine();

    }   

    if (in3 == "+") 

    {

         z = x+y;

        Console.WriteLine("the sum is : " + z);

    }

   else if (in3 == "-")

    {

        z = x-y;

        Console.WriteLine("the difference is : " + z);

    }

    else if (in3 == "/")

    {

        z = x/y;

        Console.WriteLine("the quotient is : " + z);

    }

    else if (in3=="*")

    {

        z = x*y;

        Console.WriteLine("the product is : " + z);

    }

    else if (in3 == "++X")

    {

        z = ++x;

        Console.WriteLine("the prefix increment of X : " + z);

    }

    else if (in3== "X++")

    {

        z = x++;

        Console.WriteLine("the postfix increment of X : " + z);

    }

    else if (in3=="Y++")

    {

        z = y++;

        Console.WriteLine("the postfix increment of Y : " + z);

    }

    else if (in3=="++Y")

    {

        z = ++y;

        Console.WriteLine("the prefix increment of Y : " + z);

    }

    else if (in3=="X--")

    {

        z = x--;

        Console.WriteLine("the postfix decrement of X: " + z);

    }

    else if (in3 == "--X")

    {

        z = --x;

        Console.WriteLine("the prefix decrement of X: " + z);

    }

    else if (in3 == "Y--")

    {

        z = y--;

        Console.WriteLine("the postfix decrement of Y: " + z);

    }

    else if (in3 == "--Y")

    {

        z = --y;

        Console.WriteLine("the prefix decrement of Y : " + z);

    }

​

}   

    string ex;      

    const string co12 = "if you would like to leave simply type exit below.";   

    Console.WriteLine(co12);        

    ex =Console.ReadLine();

        if(ex == "exit")

        {

            Console.WriteLine("you have now exited the program");

        }

        else{

            Console.WriteLine("ERROR");

        }

    }

}

​