Chapter 8

Which of the following array declarations would enable you to store the high and low temperatures for each day of one full week? a. int temp1Lo, temp2Lo, temp3Lo, temp4Lo, temp5Lo, temp6Lo, temp7Lo, temp1Hi, temp2Hi, temp3Hi, temp4Hi, temp5Hi, temp6Hi, temp7Hi; b. int temp [7, 2] = new int [7, 2]; c. temp int [ , ] = new temp [7, 2]; d. int [ , ] temp = new temp [7, 2]; e. int [ , ] temp = new temp [8, 3];

Assume a two-dimensional array called num is declared to hold four rows and seven columns. Which of the following statements correctly assigns the value 100 to the third physical column of each row? a. for (x = 0; x < 3; ++x) num [x, 2] = 100 b. for (x = 0; x < 4; ++x) num [x, 2] = 100; c. for (x = 1; x < 4; ++x) num [x, 2] = 100; d. for (x = 1; x < 5; ++x) num [x, 2] = 100; e. none of the above

Choose the statement that does not apply to the following declaration: double \([, 1]\) totalcostofItems \(=\) \\[\\{\\{109.95,169.95,1.50,89.95\\}\\{27.9,18.6,26.8,98.5\\}\\}\\] a. declares a two-dimensional array of floating-point values b. establishes the maximum number of rows as 4 c. sets the array element totalcostofItems [0,1] to 169.95 d. declares an area in memory where data of double type can be stored e. all are correct

Using the following declaration: char [ , ] n = {{'a', 'b', 'c', 'd', 'e'}, {'f', 'g', 'h', 'i', 'j'}}; What does n[1, 1] refer to? a. a b. f c. b d. g e. none of the above

A two-dimensional array is a list of data items that . a. all have the same type b. all have different names c. all are integers d. all are originally set to null ('\0') e. none of the above

How many components are allocated by the following statement? double [, ] values = new double [3, 2]; a. 32 b. 3 c. 5 d. 6 e. none of the above

If you declare an array as int [, ] anArray = new int [5, 3]; you can double the value stored in anArray[2, 1] with the statement: a. anArray[2, 1] = anArray[5, 1] * 2; b. anArray = anArray * 2; c. anArray[2, 1] *= anArray[2, 1] * 2; d. anArray[2, 1] *= 2; e. none of the above

With the following declaration: int [ , ] points = {{300, 100, 200, 400, 600}, {550, 700, 900, 800, 100}}; The statement points[1, 3] = points[1, 3] + 10; will a. replace the 300 amount with 310 and 900 with 910 b. replace the 500 amount with 510 c. replace the 900 amount with 910 d. replace the 800 amount with 810 e. none of the above

With the following declaration: int [ , ] points = {{300, 100, 200, 400, 600}, {550, 700, 900, 200, 100}}; The statement points[0, 4] = points[0, 4-2]; will a. replace the 400 amount with 2 b. replace the 300 and 600 with 2 c. replace the 600 with 200 d. result in an error e. none of the above

With the following declaration: int [ , ] points = {{300, 100, 200, 400, 600}, {550, 700, 900, 200, 100}}; The statement Console.Write(points[1, 2] + points[0, 3]); will a. display 900400 b. display 1300 c. display "points[1, 2] + points[0, 3]" d. result in an error e. none of the above

When you pass an element from an ArrayList to a method, the method receives: a. a copy of the ArrayList b. the address of the ArrayList c. a copy of the value in the element of the ArrayList d. the address of the element in the ArrayList e. none of the above

When you pass the entire ArrayList to a method, the method receives: a. a copy of the ArrayList b. the address of the ArrayList c. a copy of the first value in the ArrayList d. the address of each of the elements in the ArrayList e. none of the above

To convert all the uppercase letters in a string to their lowercase counterpart, you can use __________ the method of the string class. a. IsLower( ) b. ConvertLower( ) c. Lower( ) d. ToLower( ) e. none of the above

Which method in the ArrayList class can be used to place a value onto the end of the ArrayList? a. AddLast( ) b. AddLastIndex( ) c. Add( ) d. Insert( ) e. none of the above

Which method in the ArrayList class can be used to get or set the number of elements that an ArrayList can contain? a. Length( ) b. Size( ) c. Dimension( ) d. Rank( ) e. Capacity( )

A correct method call to a method that has the following heading would be: int result(int[ , ] anArray, int num) a. Console.Write(result(anArray, 3)); b. result(anArray, 30); c. Console.Write(result(anArray[ ], 3)); d. result(anArray[ ], 30); e. none of the above

With two-dimensional arrays a limitation on the foreach statement is that it can: a. only be used for read-only access b. only be used with integral type arrays c. not be used with multidimensional arrays d. only be used with arrays smaller than 1000 elements e. not be used with dynamic arrays

In order to retrieve a value stored in an object of the Queue class, you would use which method? a. Pop( ); b. Push( ); c. Dequeue( ); d. Enqueue( ); e. none of the above

Use the following string to answer questions a through e. string sValue \(=\) "Today is the first day of \(+\) "the rest of your life." a. Create a new string that has all lowercase characters except the word day. Day should be all uppercase. b. Create a new string array that contains the eight elements. Each word from the sValue string should be in a separate array cell. c. Remove the period from the last array element created in Step b. Display the contents of the new array verifying its removal. d. Surround the sValue string with three asterisks on each end. e. Replace the word first with the word best in the sValue string.

Using the following declaration: \\[\text { int }[,] \text { anArray }=\\{\\{34,55,67,89,99\\},\\{22,68,11,19,45\\}\\}\\] What would be the result of each of the following output statements? a. Console.WriteLine(anArray.Length); b. Console.WriteLine(anArray[1, 2]); c. Console.WriteLine(anArray[0, anArray.GetLength(0) - 2]); d. Console.WriteLine(anArray[0, 2 + 1] * anArray[0, 0]); e. Console.WriteLine(anArray.Rank);

Using the following declarations, write solutions for Steps a through e. int [ , ] cArray = new int [2, 3]; string [ , , ] dArray = new string [5, 2, 6]; a. Write a foreach loop to display the contents of cArray. b. Write a for loop to increment each element in cArray by 5. c. Write a foreach loop to display the contents of dArray. d. Can you use a foreach loop to initialize all elements of dArray with zero? If so, show your code. If not, explain why. e. Write a for loop to initialize all elements in dArray to zero.

Create array declarations for the following problem specifications. a. An array to hold the name of the largest 3 cities for 5 states. Initialize with the 5 states closest to your campus. b. A single array to hold the names of 10 people. You should be able to reference each person’s first name without having to use string manipulation methods to split the data apart. c. A single array to store keys for five exams each consisting of 15 true/false questions.

Explain the difference between the .NET Hashtable and Dictionary classes.