COMPSCI 61A Lecture Notes - Lecture 22: Peon, Bourgeoisie, Init

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COMPSCI 61A Full Course Notes

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Attribute assignment statements can change the first and rest attributes of a link. The rest of a linked list can contain the linked list as a sub-list. Self. elf = worker return bourgeoisie. greeting return self. greeting + , i work". Instance attributes are found before class attributes: class attributes are inherited. Return i gather wealth": does not have instance attribute of greeting, checks in class, evalutes that. Morse code: signaling protocol that transmits messages by sequences of signals implement morse so that decode works correctly tree = [b for b in tree. branches. if b. label == signal][0] for signal in signals: Leaves = [b for b in tree. branches if not b. branches] assert len(leaves) == 1. Attribute assignment assigns to the object immediately to the left of the dot. Abcde = { a": . -", b", -", c": -. -. ", d": -" def decode(signals, tree): def morse(code): Match = [b for b in tree. branches if b. entry == signal] if match:

Related Questions

Given the following main program

#main
a = [5,2,9,6,3] doubleList(a) print a

Implement the function named doubleList that takes one list argument and modifies the list so that each element in the list is doubled. The statement print(a) in the main program will then have to print [10,4,18,12,6]
Given the following main program

#main
a = [5,2,9,6,3]
b = reversedList(a) print b
print a

Implement the function named reversedList that takes one list argument and returns a list that contains the elements in the list argument in reverse order. The statement print(b) in the main program will then have to print [3,6,9,2,5]. The statement print(a) must print the original list [5,2,9,6,3] unaffected. This means your function should not modify the list argument.
Given the following main program

#main
a = [5,2,9,6,3] reverseList(a) print a

Implement the function named reverseList that takes one list argument and reverses the list so that the modified list contains the same elements in reverse order. The statement print(a) in the main program will then have to print [3,6,9,2,5]
What is the return value of the functions doubleList, reversedList and reverseList in questions 1, 2, and 3 above?

Given the following main program

#main
a = [5,2,9,6,3]
b = evenElements(a) print b

Implement the function named evenElements that takes one list argument and returns a list that contains the elements in the list argument that are even integers. The statement print(b) in the main program will then have to print [2,6]. What is the return value of the function? Your function should not modify the list argument.
Given the following main program

#main
a = [5, 2, 9, 6, 3, 7, 19, 4, 8, 17, 21, 20, 15] removeOddElements(a)
print a

Implement the function named removeOddElements that takes one list argument and modifies the list so that all odd integers in the list are removed. The statement print(a) in the main program will then have to print [2,6,4,8,20]. What is the return value of the function?
Part A
#Main program A=[5,8,2,0,-5,3] n=-5
answer = isFound(A, n) if answer == True:

print "The integer is found in the list" else:

print "The integer is not found in the list."

Consider the main program shown above. Write a Python function named isFound that takes a list of integers and an integer as arguments and returns True if the integer is found in the list; otherwise it returns False.

Remark: You are NOT allowed to use the in operator or any other built in function when you write this function. Instead, you must write a loop to go through the elements of the list.

Part B

Give the following main program

#main
A = [5,2,9,6,3]
B = [2,4,3,9,7,1,6,5]
flag = isList1InList2(A, B) if flag:

print "The list", A, "is contained in the list", B else:

print "The list", A, "is not contained in the list", B

Implement the function named isList1InList2 that takes two list arguments and returns True if and only if each element of the first list argument are found in the second list argument; otherwise it returns False.

Remark: You are NOT allowed to use the in operator or any other built in function when you write this function. Instead, if you wish, you can use the function you wrote in Part A.

For the lists shown in the main program, your function must return True because each element of list A is found in list B.

A given List is known as Palindrome List if the reverse of the List contains the same elements in the same order of the original List. For example the List of integers [2, 5, 0, 3, 3, 0, 5, 2] is a Palindrome because the reverse of the List which is [2, 5, 0, 3, 3, 0, 5, 2] contains the same elements in the same order as the given List. However the List [1, 2, '2', 1] is not Palindrome because its reverse which is [1, '2', 2, 1] does not contain the same elements in the same order as the given List.

Write a Python function named isPalindrome that takes a List as argument and returns True if the argument is a Palindrome List; otherwise it returns False. You don't need to write the main program; just write the function. If you would like to test your function, then it is ok to write the main program too but you will not get any mark for the main program.
Given your function in question #7 above, what is the output of the following code: a=[]

b = [5,2,9,6,3]

print isList1InList2(a,b)
Given your function in question #7 above, what is the output of the following code:

a=[]
b=[]
print isList1InList2(a,b)
Given your function in question #7 above, what is the output of the following code: a = [5,2,9,6,3]

b=[]

print isList1InList2(a,b)

Given the following main program

#main
a=[]
n = readListElements(a)
print "The user entered", n, "elements to the list" print a

Implement the function named readListElements that takes one list argument and modifies the list by repeatedly asking the user to enter integer values and then appending them to the list. The process stops when the user enters -1000. The stopping value -1000 should not be appended to the list. Moreover your function must count the appended elements and return it. Example if the user enters the integers 31, -4, 9, 1,-1000 then your function must modify the list a to a = [31, -4, 9, 1] and return the number elements added which is 4.
Write a function named createRandomList that takes an integer argument n and returns a list with n elements. The elements must be random numbers in the range [0,100]

Given the following main program:

#main

   n = int(input("How many elements do you want in your list? "))
   a = createList(n)
   s1 = sumOfElementsAtEvenIndexes(a)
   print s1

   s2 = sumOfElementsAtOddIndexes(a)
   print s2
   s3 = sumOfAllElements1(a)
   print s3

   s4 = sumOfEvenElements(a)
   print s4
   s5 = sumOfOddElements(a)
   print s5

   s6 = sumOfAllElements2(a)
   print s6
   if (s3 != s6):

         print "Something is wrong in your program."
   else:

         print "Looks like you have done a good job."

Implement the functions as follows:

createList: returns a list object with n elements. The elements are generated randomly so that each element is in the range [15,45]
sumOfElementsAtEvenIndexes: returns the sum of the elements at even indexes. Use a for loop or a while loop.
sumOfElementsAtOddIndexes: returns the sum of the elements at odd indexes. Use a for loop or a while loop.
sumOfAllElements_A: returns the sum of all the elements in the list using the functionssumOfElementsAtEvenIndexes and sumOfElementsAtOddIndexes. Here you are NOT allowed to use any loop; instead make function calls as described.
sumOfEvenElements: returns the sum of the even integer elements in the list. Use a for loop or a while loop.
sumOfOddElements: returns the sum of the odd integer elements in the list. Use a for loop or a while loop.
sumOfAllElementsB: returns the sum of all the elements in the list using the functions sumOfEvenElements and sumOfOddElements. Here you are NOT allowed to use any loop; instead make function calls as described.

17. Most data compression algorithms like winzip, gzip, lzip and etc are based on the frequency distribution of characters in a given string. Write a function named getFreqDistribution that takes a string argument and returns a LIST that has length 26 such that the first element of the list is the number of appearance of 'a' or 'A' in the string, the second element is number of appearance of 'b' or 'B', and so on so forth.

I'm studying python 2 and have a lot of troubles with solving these homework questions.

grayelk171

8. Write a class called WordSet representing a set of String objects which can contain an arbitrary number of strings, limited only by the memory available to the Java Virtual Machine. A set is a collection of elements, however, unlike a list, a set cannot contain duplicate elements. Therefore, as its name implies, a WordSet object cannot contain duplicate Strings that is, if one attempts to da String to a Wordset, and the wordset already contains an element which is equal to this string, the attempt will fail and the state of the Wordset will not change. All String comparisons performed in the methods defined in the Wordset class are done in a Case SENSITIVE manner. Note that in the method descriptions below, the phrase "this Wordset" means "the Wordset on which the method in question is called." Your Wordset class MUST provide the following INSTANCE methods • A constructor, which takes no parameters and initializes the new Wordset ohject so that it contains no elements • A method called add(), which takes as its only parameter a string and returns a value of type boolean. If this Wordset already contains a string which is equal to the parameter string, or the parameter String is null, then the state of this Wordset does not change and the method return false; otherwise, the parameter String is added to this Wordset. and the method returns true. • A method called remove().which takes as its only parameter a string and returns a value of type boolean. If this wordSet contains a string which is equal to the parameter String this string is removed from the WordSet and the method returns true. On the other hand, if the string parameter is null or this Wordset does not contain a string which is equal to the parameter string, then the state of this wordset does not change, and the method return false. • A method called get.size(), which takes no parameters and returns the number of strings currently stored in this Wordset. This method MUST NOT change the state of this Wordset. • A method called isMember(). which takes as its only parameter a string and retumsa value of type boolean which is true if this wordset contains the parameter String false otherwise. If the parameter String is null, this method also return false. This method MUST NOT change the state of this wordset. • A method called computebirrerence().which takes as its only parameter a Wordset and returns a new Wordset representing the difference between this wordset and the parameter Wordset: in other words, the WordSet returned by this method contains all the strings that are in this wordset, but not in the parameter Wordset. If the parameter Wordset contains all the elements of this WordSet or this WordSet contains no elements, then this method returns a new Wordset containing no elements. Finally, if the parameter Wordset is null or contains ne strings, then this method returns a new wordset which contains all the elements of this wordset. This method MUST NOT change the state of this wordset or the parameter Wordset. • A method called tostring , which takes the parameters and turns a string which is the textual representation of this wordset. This textual representation consists of the concatena tion of the following clements - The String - The text representation of each clement in the WordSet; cach pair of adjacent clements is separated by the String", but this String MUST NOT appear before the first clement or after the last element - The String") The order in which the elements of this Wordset appear in the textual representation generated by the tostring() method does not matter. If the WordSet contains to Brings, then the textual representation returned by this method is ". Note that you MUST respect proper encapsulation practices that is, the attributes and methods of your class MUST be declared using the proper visibility modifier NINT Um an array list (of string) to keep track of the string stored in a wordt ob joot Is there a method defined in the Array loist class which determines whether in clementis already wored in an array ist, and which will do a case-sensitive comparison when liked on an Arraylint of strings? See the pages 24-26 of this examination for information about potentially useful methods defined by the ArrayList class WRITE YOUR Wordset CLASS IN THE SPACE BELOW:

Grade 9 Science – Lab Safety & Equipment Woksheet

Part A: Highlight ‘T’ for TRUE OR ‘F’ for FALSE for each of the following questions. (K - 35)

1. T F Broken glassware should be swept up immediately and placed in the garbage bin.
2. T F Eyeglasses or contact lenses are an acceptable substitute for googles during an experiment.
3. T F If you arrive at class to find a spilled liquid on your desk, you should assume it is water and wipe
it up with paper towels.
4. T F Students with long hair must tie it back when using Bunsen burners.
5. T F If you take too much of the chemicals needed for an experiment, put it back into the container you
got it from.
6. T F Class B fires are those related to electrical equipment.
7. T F Discard all solid waste by rinsing it down the sink.
8. T F You may consume food and drinks during a lab, as long as it is kept at a safe distance from
chemicals.
9. T F If asked to detect the odour of a chemical in the lab, the student should inhale a deep breath of the
chemical.
10. T F If your clothing were to catch on fire, your first step should be to STOP, DROP and ROLL.
11. T F When using a fire extinguisher, aim at the top of the fire. The chemical in the extinguisher will
fall and put out the flames.
12. T F When heating chemicals in a test tube, heat from the bottom up, aiming the test tube at the
ceiling, and keep the test tube still.
13. T F It is ok to take off my safety goggles if it’s just for a second while I write something down.
14. T F If any chemical makes contact with your eye, wash it immediately at the eyewash station for
fifteen minutes. If you should spill chemicals on your skin, place the affected area under water
immediately.
15. T F Always read through each activity before you begin.
16. T F If you are unsure about any part of the procedure for an experiment, you should figure it out
yourself. Asking the teacher for clarification will result in a lower mark due to lack of preparation.
17. T F It is acceptable to sit during very long experiments.
18. T F It is ok if I don’t know where the lab safety equipment is since I can just ask someone later.
19. T F Be sure to tell your teacher about any accident, broken equipment, or injury that occurs during
class; no matter how minor.
20. T F When working with chemicals, keep pens and pencils away from your mouth.
21. T F In warmer months, it is acceptable to wear sandals during an experiment.
22. T F Determine whether your equipment is cool enough to disassemble by placing the back of your
hand near it.
23. T F Loose-fitting, long-sleeved shirts should be worn during experiments to protect your arms from
burns and chemical splashes.
24. T F If you must retrieve materials during a lab, it is acceptable to leave your Bunsen burner unattended
as long as it is set to a yellow flame.
25. T F To avoid an injury when heating materials, always place a stopper or tight-fitting lid on the
container being heated.
26. T F If a student uses the last of the chemicals in an experiment, it is their responsibility to go into the
storeroom to retrieve an additional quantity of that chemical.
27. T F Always leave your work area clean and dry before leaving the lab and make sure equipment and
glassware is returned clean to its proper place.
28. T F Horseplay is O.K. during a lab as long as no one is getting hurt.
29. T F It is never advisable to place a thermometer in an open flame.
30. T F To cool hot glassware, run cold water over it.
31. T F Class A fires can be extinguished with water.
32. T F Class D fires must be extinguished with water.
33. T F Keep equipment away from the edge of the lab bench.
34. T F If your eye itches while you are working with chemicals, you should rub it with your hands.
35. T F WHMIS stands for warning hazardous materials information symbols.

jhonny

COMPSCI 61A Lecture Notes - Lecture 22: Peon, Bourgeoisie, Init

COMPSCI 61A Full Course Notes

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