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Recommended textbook solutionsService Management: Operations, Strategy, and Information Technology7th EditionJames Fitzsimmons, Mona Fitzsimmons 103 solutions Information Technology Project Management: Providing Measurable Organizational Value5th EditionJack T. Marchewka 346 solutions Introduction to Algorithms3rd EditionCharles E. Leiserson, Clifford Stein, Ronald L. Rivest, Thomas H. Cormen 720 solutions Fundamentals of Database Systems7th EditionRamez Elmasri, Shamkant B. Navathe 687 solutions Recommended textbook solutionsIntroduction to Algorithms3rd EditionCharles E. Leiserson, Clifford Stein, Ronald L. Rivest, Thomas H. Cormen 720 solutions Information Technology Project Management: Providing Measurable Organizational Value5th EditionJack T. Marchewka 346 solutions Fundamentals of Database Systems7th EditionRamez Elmasri, Shamkant B. Navathe 687 solutions Information Technology Project Management: Providing Measurable Organizational Value5th EditionJack T. Marchewka 346 solutions Upgrade to remove ads Only SGD 41.99/year
Terms in this set (49)What will the println statement in the following program segment
display? 5 What will the println statement in the following program segment display? 6 In the expression number++, the operator ++ is in what mode? postfix What is each repetition of a loop known as? iteration This is a variable that controls the number of iterations performed by a loop. loop control variable The while loop is this type of loop. pretest The do-while loop is this type of loop. posttest The for loop is this type of loop. pretest This type of loop has no way of ending and repeats until the program is interrupted. infinite This type of loop always executes at least once. do-while This expression is executed by the for loop only once, regardless of the number of iterations. initialization expression This is a variable that keeps a running total. accumulator This is a special value that signals when there are no more items from a list of items to be processed. This value cannot be mistaken as an item from the list. sentinel To open a file for writing, you use the following class. PrintWriter To open a file for reading, you use the following classes. File and Scanner When a program is finished using a file, it should do this. Close the file This class allows you to use the print and println methods to write data to a file. PrintWriter This class allows you to read a line from a file. Scanner The while loop is a pretest loop. True The do-while loop is a pretest loop. False The for loop is a posttest loop. False It is not necessary to initialize accumulator variables. False One limitations of the for loop is that only one variable may be initialized in the initialization expression. False A variable may be defined in the initialization expression of the for loop. True In a nested loop, the inner loop goes through all of its iterations for every iteration of the outer loop. True To calculate the total number of iterations of a nested loop, add the number of iterations of all the loops. False Briefly describe the difference between the prefix and postfix modes used by the increment and decrement operators. In postfix mode the operator is placed after the operand. In prefix mode the operator is placed before the variable operand. Postfix mode causes the increment or decrement operation to happen after the value of the variable is used in the expression. Prefix mode causes the increment or decrement to happen first. Why should you indent the statements in the body of a loop? A pretest loop tests its condition before each iteration. A posttest loop tests its condition after each iteration. A posttest loop will always execute at least once. Describe the difference between pretest loops and posttest loops. A pretest loop tests its test expression before each iteration. A posttest loop tests its test expression after each iteration. Why are the statements in the body of a loop called conditionally executed statements? Because the loop executes them only under the condition that its test expression is true. Describe the difference between the while loop and the do-while loop. The while loop is a pretest loop and the do-while loop is a posttest loop. Which loop should you use in situations where you want the loop to repeat until the boolean expression is false, and the loop should not execute if the test expression is false to begin with? The while loop. Which loop should you use in situations where you want the loop to repeat until the boolean expression is false, but the loop should execute at least once? The do-while loop. Which loop should you use when you know the number of required iterations? The for loop. Why is it critical that accumulator variables are properly initialized? An accumulator is used to keep a running total of numbers. In a loop, a value is usually added to the current value of the accumulator. If it is not properly initialized, it will not contain the correct total. What is an infinite loop? Write the code for an infinite loop. A loop that has no way of stopping. Here is an example: Describe a programming problem that would require the use of an accumulator. There are many possible examples. A program that asks the user to enter a business's daily sales for a number of days, and then displays the total sales is one example. What does it mean to let the user control a loop? The loop terminates after the user has entered a specific value. What is the advantage of using a sentinel? Sometimes the user has a list of input values that is very long, and doesn't know the number of items there are. When the sentinel value is entered, it signals the end of the list, and the user doesn't have to count the number of items in the list. Why must the value chosen for use a sentinel be carefully selected? So it cannot be mistaken as a member of the list. Describe a programming problem requiring the use of nested loops. There are many possible examples. One example is a program that asks for the average temperature for each month, for a period of five years. The outer loop would iterate once for each year and the inner loop would iterate once for each month. How does a file buffer increase a program's performance? When a program writes data to a file, that data is first written to the buffer. When the buffer is filled, all the information stored there is written to the file. This technique increases the system's performance because writing data to memory is faster than writing it to a disk. Why should a program close a file when it's finished using it? Closing a file writes any unsaved data remaining in the file buffer. What is a file's read position? Where is the read position when a file is first opened for reading? The read position is the position of the next item to be read. When the file is opened, its read position is set to the first item in the file. When writing data to a file, what is the difference between the print and the println methods? After the println method writes its data, it writes a newline character. The print method does not write the newline character. What does a scanner class's hasNext method return when the end of the file has been reached? false What is a potential error that can occur when a file is opened for reading? The file does not exist. What does it mean to append data to a file? To write the data to the end of the file's existing contents. How do you open a file so that new data will be written to the end of the file's existing data? You create an instance of the FileWriter class to open the file. You pass the name of the file (a string) as the constructor's first argument, and the boolean value true as the second argument. Then, when you create an instance of the PrintWriter class, you pass a reference to the FileWriter object as an argument to the PrintWriter constructor. The file will not be erased if it already exists and new data will be written to the end of the file. Sets with similar termsChapter 4 Java Loops and Files84 terms NightCloudSurfer Chapter 546 terms cboyer1996 Java chapter 426 terms waking19 Chapter 5: Starting out with C++ Definitions44 terms carolina_ramirez520 Sets found in the same folderTest 2 review40 terms orc_mischiefPLUS Chapter 9 review40 terms orc_mischiefPLUS CPS Chapter 3 MC/TF/Short Answer31 terms abbyxm17 Chapter 7 review48 terms orc_mischiefPLUS Other sets by this creatorFinal Exam - Intro to Neuro87 terms abbyxm17 Dev. Psych - Exam 357 terms abbyxm17 Human Phys Unit 52 terms abbyxm17 Human Phys Exam 4 Practice Questions17 terms abbyxm17 Verified questionsCOMPUTER SCIENCE A design technique that helps to reduce the duplication of code within a program and is a benefit of using functions is __________. a. code reuse b. divide and conquer c. debugging d. facilitation of teamwork Verified answer COMPUTER SCIENCE The kth quantiles of an n-element set are the k - 1 order statistics that divide the sorted set into k equal-sized sets (to within 1). Give an O(n lg k)-time algorithm to list the kth quantiles of a set. Verified answer COMPUTER SCIENCE Give implementation-level descriptions of Turing machines that decide the following languages over the alphabet {0,1}. $^\mathrm{A}{\mathrm{a}}$. {w| w contains an equal number of 0s and 1s}, b. {w| w contains twice as many 0s as 1s}, c. {w| w does not contain twice as many 0s as 1s}. Verified answer COMPUTER SCIENCE Object is to class as a. circle is to square, b. house is to blueprint, c. blueprint is to house, d. bicycle is to car, e. car is to bicycle. Verified answer Recommended textbook solutionsInformation Technology Project Management: Providing Measurable Organizational Value5th EditionJack T. Marchewka 346 solutions Fundamentals of Database Systems7th EditionRamez Elmasri, Shamkant B. Navathe 687 solutions Computer Organization and Design MIPS Edition: The Hardware/Software Interface5th EditionDavid A. Patterson, John L. Hennessy 220 solutions Introduction to the Theory of Computation3rd EditionMichael Sipser 389 solutions Other Quizlet setsBio Exam 3 Study Guide77 terms elhombreverde Miriam Lines78 terms WAveri1 Quiz Questions45 terms zbuanno Related questionsQUESTION Which HTML tag should you use to define a hot spot region on an image map ? 15 answers QUESTION int b [9999] = {23}; will initialize all elements of the array b to 23 2 answers QUESTION In HTML, JavaScript code must be inserted between <script> and </script> tags. 2 answers QUESTION What operator could be used if you wanted to constantly query the Bitcoin API but then stop once it reached a certain value? 2 answers What is the difference between pretest loops and posttest loops?pretest loop: A loop that tests the condition before each iteration. posttest loop: A loop that tests the condition after each iteration. What is the difference between a pretest and a posttest?Typically, a pretest is given to students at the beginning of a course to determine their initial understanding of the measures stated in the learning objectives, and posttest is conducted just after completion of the course to determine what the students have learned. What is the difference between a pretest loop and a posttest loop give an example of each loop?the statements in Do/Loop are skipped. is executed at least once, since the condition is at the bottom of the loop. ... Explain difference between a pretest and a posttest in a Do/Loop.. Which loop is the posttest loop?The do-while loop is a posttest loop. This means it does not test its expression until it has completed an iteration. As a result, the do-while loop always performs at least one iteration, even if the expression is false to begin with. DoDo while loops check the condition after the block of code is executed. This control structure can be known as a post-test loop. This means the do-while loop is an exit-condition loop. However a while loop will test the condition before the code within the block is executed.
Which loops are pre test?The while and for statements are pretest loops; that is, they test the condition first and at the beginning of each pass through the loop. Java also provides a posttest loop: the do - while statement. This type of loop is useful when you need to run the body of the loop at least once.
Which loop is a post test condition loop?The second form of conditional loop is known as a post-test conditional loop. This form of repetition will check the condition after the commands have been executed, initiating another execution of the loop if the condition is not met.
What is pretest and post test loop?Pretest loop runs zero(0) or more times. while (condition) { /* ... */ } Post test loop runs one(1) or more times but at least once.
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