1. Determine whether the condition is true or false. Assume a = 2 and b = 3.
((a = b) Or Not (b < a)) And ((a < b) Or (b = a + 1))
2. Determine whether or not the two conditions are equivalent - that is, whether they will be true or false for exactly the same values of the variables appearing in them.
Not ((a = b) Or (a = c)); (a <> b) And (a <> c)
3. Determine the output displayed in the text box when the button is clicked. Assume the response is B
Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
Dim letter As String
letter = InputBox("Enter A, B, or C.")
letter = letter.ToUpper
If letter = "A" Then
txtOutput.Text = "A, my name is Alice."
ElseIf letter = "B" Then
txtOutput.Text = "To be, or not to be."
ElseIf letter = "C" Then
txtOutput.Text = "Oh, say, can you see."
Else
txtOutput.Text = "Not a valid letter."
End If
End Sub
4. Identify the errors.
Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
'Is your program correct?
Dim query, answer1, answer2 As String
query = "Are you sure everything in your program is correct?"
answer1 = InputBox(query)
answer1 = answer1.ToUpper.Substring(0, 1)
If answer1 = "N" Then
txtOutput.Text = "Don't patch bad code, rewrite it."
Else
query = "Does your program run correctly?"
answer2 = InputBox(query)
answer2 = answer2.ToUpper.Substring(0, 1)
If answer2 = "Y" Then
txtOutput.Text = "Congratulations."
Else
txtOutput.Text = "Something you are sure about is wrong."
End If
End Sub
5. The current calendar, called the Gregorian calendar, was introduced in 1582. Every year divisible by four was declared to be a leap year, with the exception of the years ending in 00 (that is those divisible by 100) and not divisible by 400. For instance, the years 1600 and 2000 are leap years, but 1700, 1800, and 1900 are not. Write a program that requests a year as input and states whether it is a leap year. (Test the program on the years 2008, 2009, 1900, and 2000.)
6. For each of the responses shown in the parentheses, determine the output displayed in the text box when the button is clicked.
Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
Dim yearENIAC As Integer
'Ask question and obtain answer
Dim message As String
message = "In what year was the ENIAC computer completed?"
yearENIAC = CInt(InputBox(message))
'Respond to answer
Select Case yearENIAC
Case 1945
txtOutput.Text = "Correct."
Case 1943 To 1947
txtOutput.Text = "Close, 1945."
Case Is < 1943
txtOutput.Text = "Sorry, 1945. Work on the ENIAC " & _
"began in June 1943."
Case Is > 1947
txtOutput.Text = "No, 1945. By then IBM had built " & _
"a stored-program computer."
End Select
End Sub
(1940, 1945, 1950)
7. Rewrite the code using a Select Case block.
If a = 1 Then
lstOutput.Items.Add("lambs")
End If
If ((a <= 3) And (a < 4)) Then
lstOutput.Items.Add("eat")
End If
If ((a = 5) Or (a > 7)) Then
lstOutput.Items.Add("ivy")
End If