Introduction to Programming Quiz (CodeHS) PDF

12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS 1.21.1: Introduction to Programming Quiz Question: 1 What does the mystery function do? function mystery() { while (noBallsPresent(...

12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS 1.21.1: Introduction to Programming Quiz Question: 1 What does the mystery function do? function mystery() { while (noBallsPresent()) { move(); } } ✔ Karel moves until it is on a ball If there is no ball present, Karel will move one time and stop. Karel moves until it puts down a ball Karel checks if there is no ball on the current spot and then moves once Question: 2 Which of the following is not a valid condition to go in an if statement for Karel? ballsPresent() frontIsClear() leftIsBlocked() ✔ turnLeft() Question: 3 Say Karel is on a location with one tennis ball. After the following code runs, how many tennis balls will there be at that location? for (var i = 0; i < 3; i++) { if (ballsPresent()) { takeBall(); https://codehs.com/library/printable_solution_references/assignment/146754203 1/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS } else { putBall(); putBall(); } } 0 ✔ 1 2 6 Question: 4 What condition should be used in this while loop to get Karel to pick up all the tennis balls on the current location? while (________) { takeBall(); } noBallsPresent() ✔ ballsPresent() frontIsClear() takeBall() Question: 5 Why does a programmer indent their code? Helps show the structure of the code. Easier for other people to understand. A key part of good programming style! ✔ All of the above Question: 6 https://codehs.com/library/printable_solution_references/assignment/146754203 2/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS How can we teach Karel new commands? For loop While loop ✔ Define a new function The start function Question: 7 Say you want to write a program to have Karel put down 300 tennis balls. Which control structure would you use? If statement While loop ✔ For loop Nested while loop Question: 8 Super Karel starts at Street 1, Avenue 1, facing East in a 5x5 world. What will happen after this code runs? move(); move(); turnRight(); move(); Karel ends on street 1, avenue 3 Karel ends on street 2, avenue 3 This code won’t run because of a syntax error ✔ Karel will crash into a wall Question: 9 Karel starts at Street 1, Avenue 1, facing East in a 5x5 world. What will happen after this code runs? https://codehs.com/library/printable_solution_references/assignment/146754203 3/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS move(); putball(); move(); move(); move(); move(); move(); Karel will end on Street 1, Avenue 2 Karel will end on Street 1, Avenue 7 ✔ This code won’t run because of a syntax error Karel will crash into a wall Question: 10 What is top down design? Top down design is a way of designing your program by starting ✔ with the biggest problem and breaking it down into smaller and smaller pieces that are easier to solve. Top down design is a way that you can create designs on a computer to put on a web page Top down design is a way of designing your programs starting with the individual commands first Top down design is a way to use loops and if statements to decompose the problem Question: 11 How can we improve the following program? function start() { move(); move(); move(); move(); move(); move(); move(); https://codehs.com/library/printable_solution_references/assignment/146754203 4/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS move(); move(); } Break down this program into more functions ✔ Use a for loop to repeat the move command Use a while loop to repeat the move command Fix the indentation of this program Question: 12 In the following code below from the Cleanup Karel example, what is the purpose of If Statement #2? // This program has Karel walk down the // row and clean up all of the tennis balls // on the way. function start() { while (frontIsClear()) { // If statement #1 if (ballsPresent()) { takeBall(); } move(); } // If statement #2 if (ballsPresent()) { takeBall(); } } To move the last time To pick up the ball that is in the last spot ✔ To pick up the ball that is in the last spot, if there is one To take the ball from all of the positions that have a ball on them Question: 13 In the following code, what would be a good Postcondition to write? https://codehs.com/library/printable_solution_references/assignment/146754203 5/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS function getOnTop() { turnLeft(); move(); turnRight(); } Karel is on a spot with a tennis ball facing north ✔ Karel ends one spot above a tennis ball facing East. Karel is on the same position but on top of a ball. Karel is facing East. Question: 14 What is the purpose of using a for loop in code? To do something if a condition is true To do something while a condition is true ✔ To repeat something a fixed number of times To make programs run faster Question: 15 Which of the following commands is a valid Karel command? move move; ✔ move(); move() Question: 16 What makes the following command an invalid Karel command? https://codehs.com/library/printable_solution_references/assignment/146754203 6/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS turnleft(); It should end in a colon rather than a semicolon ✔ The l should be a capital L It should start with a capital T This command is correct Question: 17 Which of the following is the correct way to define a turnRight function in Karel? function turnRight() { turnLeft(); ✔ turnLeft(); turnLeft(); } function turnRight() { turnRight(); turnRight(); turnRight(); } function turnRight { turnLeft(); turnLeft(); turnLeft(); } turnRight function() { turnLeft(); turnLeft(); turnLeft(); } Question: 18 Why do we use functions in Karel programs? Break down our program into smaller parts Avoid repeating code Make our program more readable ✔ All of the above Question: 19 https://codehs.com/library/printable_solution_references/assignment/146754203 7/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS If Karel starts at Street 1 and Avenue 1, facing East, where will Karel be, and what direction will Karel be facing after running the following code? (Assume the world is 10x10 in size) move(); turnLeft(); putBall(); turnLeft(); turnLeft(); turnLeft(); move(); turnLeft(); Street 3, Avenue 1, Facing North Street 1, Avenue 4, Facing North Street 1, Avenue 3, Facing South ✔ Street 1, Avenue 3, Facing North Question: 20 Karel starts at Street 1 and Avenue 1, facing East. After calling the stairStep function twice, where will Karel be and what direction will Karel be facing? (assume this is a SuperKarel program and the world is 10x10 in size) function stairStep() { move(); turnLeft(); move(); turnRight(); } Street 2, Avenue 2, Facing North ✔ Street 3, Avenue 3, Facing East Street 3, Avenue 3, Facing West Street 4, Avenue 4, Facing East Question: 21 In this code, how many times is the dance function called and how many times is it defined? https://codehs.com/library/printable_solution_references/assignment/146754203 8/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS function start() { move(); dance(); move(); move(); turnLeft(); dance(); dance(); } function dance() { turnLeft(); move(); turnLeft(); turnLeft(); move(); turnLeft(); } Called 1 time, defined 1 time Called 1 time, defined 3 times ✔ Called 3 times, defined 1 time Called 3 times, defined 3 times Question: 22 What’s wrong with this code? function start() { move(); go(); go(); } function go() { move(); move(); } function go() { https://codehs.com/library/printable_solution_references/assignment/146754203 9/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS move(); move(); } The go function is called twice The go function has a syntax error ✔ The go function has been defined twice go is not a command that Karel understands Question: 23 How many total times will Karel move in this program? function start() { move(); for (var i = 0; i < 5; i++) { move(); putBall(); } } 1 5 ✔ 6 7 Question: 24 What is wrong with this for loop? for (var i = 0, i < 10, i + 1) { move(); } A. The for loop uses commas instead of semicolons B. It should say i++ instead of i + 1 https://codehs.com/library/printable_solution_references/assignment/146754203 10/11 12/11/24, 5:56 PM Solution Reference for 1.21.1: Introduction to Programming Quiz | CodeHS A B ✔ A and B The for loop is correct Question: 25 What is the proper format for a single line comment in Karel? This is a comment ✔ // This is a comment /* This is a comment This is a comment https://codehs.com/library/printable_solution_references/assignment/146754203 11/11