Midterm Review
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Checkpoint 0
You’ve come a long way in four weeks.
Midterm Goal
I want to ensure that you are ready to go on and succeed in CS 125.
Midterm Format
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12 multiple-choice questions, mostly on code reading
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3 programming questions:
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one using arrays,
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one using multi-dimensional arrays,
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and one using strings.
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One programming question will be drawn directly from the HW125 practice problems. So use those to prepare.
Warm Up: Array Sum
Sum all values in a one-dimensional array of int values.
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String Equality
Write a function called areEquals that takes two String arguments and returns
true if the two strings are equal (that is, they contain the same characters)
and false otherwise.
Note that either first or second may be null.
If either are null you should return false, including if both are null.
What’s an algorithm?
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Eliminate the
nullcases -
Go through each
Stringcharacter by character… -
…or just read the docs.
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String Rotate Left
Write a function called rotateLeft that takes a String as its first argument and
a positive int as its second argument and rotates the String left by the given
number of characters.
What’s an algorithm?
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Create a new character array of the same size as the input
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Go through the passed string character by character
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Compute the new position for that character
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Copy the character into position in the new character array
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String Rotation Master Class
Let’s look at some ways to do HW18.
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Note that all of these passed our test suite.
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But that doesn’t mean that they are all correct.
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I’m not going to post these as part of the slide deck to avoid disseminating potentially bad solutions
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Is this your code? Probably not—it’s from last semester.
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Tic-Tac-Toe Master Class
Let’s look at some ways to do HW22.
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Note that all of these passed our test suite.
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But that doesn’t mean that they are all correct.
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I’m not going to post these as part of the slide deck to avoid disseminating potentially bad solutions
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Is this your code? Maybe. Maybe not.
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Announcements
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Next week we will hold our first midterm exam: a one-hour quiz worth 2% of your grade that cannot be dropped
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No labs as scheduled next week. Instead, we’ll hold office hours during the same times in Siebel 0403. Come to get some help preparing for the midterm.
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Today I’ll be doing one James Scholar interview session, here, now. If you want to interview me for your project this is your chance.
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Monday we will begin discussing objects!
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Office hours for MP1 continue—please get started, since it will help you prepare for the midterm exam next week