Visual Basic.NET How to Program (PDF)

242 Procedures Chapter 6
EXERCISES
Return x + y
or add the following statement at the end of the method body:
Return result
c) Error: Parameter value is redefined in the procedure definition.
Correction: Delete the declaration Dim value As Single.
d) Error: The procedure returns a value, but is defined as a Sub procedure.
Correction: Change the procedure to a Function procedure with return type Integer.
e) Error: The result of value += Sum(value - 1) is not returned by this recursive method,
resulting in a logic error.
Correction: Rewrite the statement in the Else clause as
Return value + sum(value - 1)
6.7 What is the value of x after each of the following statements is performed?
a) x = Math.Abs(7.5)
b) x = Math.Floor(7.5)
c) x = Math.Abs(0.0)
d) x = Math.Ceiling(0.0)
e) x = Math.Abs(-6.4)
f) x = Math.Ceiling(-6.4)
g) x = Math.Ceiling(-Math.Abs(-8 + Math.Floor(-5.5)))
6.8 A parking garage charges a $2.00 minimum fee to park for up to three hours. The garage
charges an additional $0.50 per hour for each hour or part thereof in excess of three hours. The maximum
charge for any given 24-hour period is $10.00. Assume that no car parks for longer than 24
hours at a time. Write a program that calculates and displays the parking charges for each customer
who parked a car in this garage yesterday. You should enter in a TextBox the hours parked for each
customer. The program should display the charge for the current customer. The program should use
the method CalculateCharges to determine the charge for each customer. Use the techniques
described in the chapter to read the Double value from a TextBox.
6.9 Write a method IntegerPower(base, exponent) that returns the value of
base exponent
For example, IntegerPower(3, 4) = 3 * 3*3*3. Assume that exponent is a positive integer
and that base is an integer. Method IntegerPower should use a For/Next loop or While loop to
control the calculation. Do not use any Math library methods or the exponentiation operator, ^. Incorporate
this method into a Windows application that reads integer values from TextBoxes for base
and exponent from the user and performs the calculation by calling method IntegerPower.
6.10 Define a method Hypotenuse that calculates the length of the hypotenuse of a right triangle
when the other two sides are given. The method should take two arguments of type Double and
return the hypotenuse as a Double. Incorporate this method into a Windows application that reads
integer values for side1 and side2 from TextBoxes and performs the calculation with the Hypotenuse
method. Determine the length of the hypotenuse for each of the following triangles: