Chapter 4 Exercises

sweetj · August 17th, 2003, 11:27 PM

Just wanted to double check my answers. Any help would be appreciated.

1.) ^

2.)

static void Main(string[] args)
        {
            int firstInt, secondInt;
            Console.WriteLine("Please enter 2 integers where the sum of the 2 are less then or equal to 10:");
            do
            {
                firstInt = Convert.ToInt32(Console.ReadLine());
                Console.WriteLine("Now enter another integer:");
                secondInt = Convert.ToInt32(Console.ReadLine());
                if (10 <= firstInt + secondInt)
                    Console.WriteLine("Both numbers must be less then 10!\nPlease enter you first number again.");
            }
            while (10 <= firstInt + secondInt);
            Console.WriteLine("Sum of both Int less then 10? {0}", firstInt + secondInt < 10);
            Console.WriteLine("Integers between 0 and 5? {0}",
                (0 <= firstInt + secondInt) && (firstInt + secondInt <= 5));
            Console.WriteLine("Bitwise AND of Integers and 10 = {0}", firstInt + secondInt & 10);
        }

3.) just a = will not get boolean comparison, and will just set i = 0 and will error out or loop forever.

4.) I didn't spend to much time trying to understand the Mandelbrot forumal so I couldn't/didn't want to do this one =P If anyone wants to post what they did and explain it that would be great :D

Chris Beach · August 18th, 2003, 07:08 AM

1) XOR
2) reading the q differently I think cause I've got:

Code:

            int myInt1,myInt2;

            Console.WriteLine("Please enter an integer:");
            do
            {
                myInt1 = Convert.ToInt32(Console.ReadLine());
                Console.WriteLine("Now enter another integer:");
                myInt2 = Convert.ToInt32(Console.ReadLine());
                if (myInt1>10 && myInt2>10)
                    Console.WriteLine("Both numbers must be less then 10!\nPlease enter you first number again.");
            }
            while (myInt1>10 && myInt2>10);

ie if both numbers entered are >10 then get them again, so (1,2),(12,2) is ok but (12,11) isn't

Chris Beach · August 18th, 2003, 07:23 AM

As for 4 well the first half:

Code:

            double realCoord, imagCoord;
            double realTemp, imagTemp, realTemp2, arg;
            double realMin=-0.6,realMax=1.77,imagMin=-1.2,imagMax=1.2;        //limits
            //get limits
            Console.WriteLine("Please enter the min Real coord {0}:",realMin);
            realMin=Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("Please enter the max Real coord {0}:",realMax);
            realMax=Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("Please enter the min Imaginary coord {0}:",imagMin);
            imagMin=Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("Please enter the max Imaginary coord {0}:",imagMax);
            imagMax=Convert.ToDouble(Console.ReadLine());

            int iterations;
            for (imagCoord=imagMax;imagCoord>=imagMin;imagCoord-=0.05)
            {
                for (realCoord=realMin; realCoord<=realMax;realCoord+=0.03)
                {
...

For the second half I think we need to alter the increments of the loops...working on that now.

Chris Beach · August 18th, 2003, 07:48 AM

ok it is the increments, first I worked out the ratio between the cords and the current increment, for the real it was 79 and for the imaginary part it was 48...so the code now looks like:

Code:

            double realCoord, imagCoord;
            double realTemp, imagTemp, realTemp2, arg;
            double realMin=-0.6,realMax=1.77,imagMin=-1.2,imagMax=1.2;        //limits
            double realInc=0.03,imagInc=0.05;                                //increments
            //get limits
            Console.WriteLine("Please enter the min Real coord {0}:",realMin);
            realMin=Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("Please enter the max Real coord {0}:",realMax);
            realMax=Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("Please enter the min Imaginary coord {0}:",imagMin);
            imagMin=Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("Please enter the max Imaginary coord {0}:",imagMax);
            imagMax=Convert.ToDouble(Console.ReadLine());
            //work out inc's
            imagInc=(imagMax-imagMin)/48;
            realInc=(realMax-realMin)/78;  //uh why not 79??

            int iterations;
            for (imagCoord=imagMax;imagCoord>=imagMin;imagCoord-=imagInc)
            {
                for (realCoord=realMin; realCoord<=realMax;realCoord+=realInc)
...

god knows why you need to change 79 to 78 but if you don't you get a gap between the lines...

sweetj · August 20th, 2003, 11:37 PM

Thanks for the response. Yea on #2 I had something similiar to that to before, but rereading the question I thought it wanted the sum of both #'s not to be greater then 10. But I could be wrong the question is a bit vague on that.