Programming Principles II

Lab 1

Problems from Informatics python course:

1. Типы данных: все задачи
2. Целочисленная арифметика: 5 задач
3. Условная инструкция: 5 задач
4. Цикл for: 5 задач
5. Действительные (вещественные) числа: 5 задач
6. Строки: 5 задач
7. Цикл while: 5 задач
8. Функция, рекурсия: 5 задач

Lab 2

Exercise 1

Create a function that returns element at index i in input list.

Sample input:

# index = 3
exercise_1([10, 3, 4, 5, 9], 3)
exercise_1([10, 3, 4, 5, 9], 4)

Sample output:

5
9

Exercise 2

Create a function that collects only values with even index from a given list

Sample input:

exercise_2([10, 3, 4, 5, 9])
exercise_2([9, 0, 12, 3, 4, 56, 9, 16])

Sample output:

[10, 4, 9]
[9, 12, 4, 9]

Exercise 3

Create a function that mutates elements to square after given index. Elements before given index do not change.

Sample input:

# index = 4, all numbers after index 4 should change to their squares
# [..., 4, 5, 9] -> [..., 4 * 4, 5 * 5, 9 * 9]
exercise_3([10, 3, 4, 5, 9], 2)
exercise_3([9, 0, 12, 3, 4, 56, 9, 16], 6)

Sample output:

[10, 3, 16, 25, 81]
[9, 0, 12, 3, 4, 56, 81, 256]

Exercise 4

Create a function that reverses a given list.

Sample input:

exercise_4([10, 3, 4, 5, 9])
exercise_4([9, 0, 12, 3, 4, 56, 9, 16])

Sample output:

[9, 5, 4, 3, 10]
[16, 9, 56, 4, 3, 12, 0, 9]

Exercise 5

Create a function that deletes elements after given index.

Sample input:

#index = 2
exercise_5([10, 3, 4, 5, 9], 1)
exercise_5([9, 0, 12, 3, 4, 56, 9, 16], 7)

Sample output:

[10]
[9, 0, 12, 3, 4, 56, 9]

Exercise 6

Create a function that inserts elements at given index and then deletes elements after given index.

Sample input:

#index insert = 2, index delete from = 4, elements to insert = [1, 2, 3]
exercise_6([10, 3, 4, 5, 9], 3, 4, [1, 2, 3])
exercise_6([9, 0, 12, 3, 4, 56, 9, 16], 7)

Sample output:

# [1, 2, 3] are inserted in position 2 -> [10, 1, 2, 3, 3, 4, 5, 9]
# elements at index 4 are deleted -> [10, 1, 2, 3]
[10]
[9, 0, 12, 3, 4, 56, 9]

Tuples

Exercise 7

Given three variables, a, b and c, swap them without using temporary variables.

Sample input:

# a = 5, b = 3, c = 2
(5, 3, 2)
('Hi', 'Ola', 'xD')

Sample output:

# a = 2, b = 5, c = 3
(2, 5, 3)
('xD', 'Hi', 'Ola')

Exercise 8

Create a function that returns both minimum and maximum value of given list.

Sample input:

exercise_8([10, 2, 5, -3, -1])
exercise_8([5, 2, 8, 4])

Sample output:

(-1, 10)
(2, 8)

Exercise 9

Create a function that returns True, if given tuple contains mutable element.

Sample input:

exercise_9((10, 2, 5, [4, 8, 2], 3, 5))
exercise_9((5, 2.5, 8, 4, 'Hi', -5, True, 6))

Sample output:

#Element at index 3 is list that can be changed
True
#All elements of given tuple are immutable objects
False

Sets

Exercise 10

Create a function that returns set with neighbor numbers of given set.

Sample input:

exercise_10({1, 5, 9})
exercise_10({2, 5, 7, 8, 10})

Sample output:

{0, 2, 4, 6, 8, 10}
{1, 3, 4, 6, 7, 8, 9, 11}

Exercise 11

Create a function that returns difference of given 2 sets. (The difference of sets A,B consists of elements that are in A but not in B).

Sample input:

#A = {1, 2, 3, 4}, B = {3, 5, 7}
exercise_11({1, 2, 3, 4}, {3, 5, 7})
exercise_11({12, 15, 16, 20, 95}, {1, 2, 3, 16, 17, 20})

Sample output:

{1, 2, 4}
{12, 15, 95}

Exercise 12

Create a function that returns a set with values from given list, if some number already exists in the set, take it to the power of two, three ... while it's in the set.

Sample input:

exercise_12([1, 2, 2])
exercise_12([1, 2, 2, 3, 4])

Sample output:

{1, 2, 4}
{1, 2, 3, 4, 16}

Exercise 13

Create a function that returns Yes, if there can be formed palindrome text using given list of number, or No, if there is no way to make a palindrome.

Sample input:

exercise_13([1,2,3,4,1])
exercise_13([1,2,3,1,2])

Sample Output:

No
Yes

Exercise 14

Create a function that returns list of numbers from the given list, that are more than given number N;

Sample input:

exercise_14([11,2,44,23], 10)
exercise_14([1,200,45,-67], 45)

Sample Output:

{11,44,23}
{200}

Exercise 15

Create a function that returns number of odd numbers that are on even positions;

Sample input:

exercise_15([0,3,11,2,44,23,4])
exercise_15([22,23,24,33,34,35])

Sample Output:

2
3

Lab 4

Disclaimer: some method definitions are not complete. Especially pay attention to passed self parameter that was omitted in method signatures. You may change method definitions to implement requirements.

Task 1

Design a class Name. Name should have 3 parameters: first_name, last_name and optional middle_name(father's name отчество).

class Name:
    pass

# example usage:
name1 = Name('Daulet', 'Kabdiyev', 'Bolatovich')
name2 = Name('Alik', 'Akhmetov')

Task 2

Design a class Student. Student has a student_id of type string and a name of type Name (from Task1).

class Student:
    pass

# example usage:
student = Student('16BD02006', Name('Daulet', 'Kabdiyev', 'Bolatovich'))

Task 3

Design a class Assistant. Assistant has a name of type Name and a year_of_study of type int. Also, implement method get_name that returns Name of assistant.

class Assistant:

    def get_name():
        pass

# example usage:
assistant = Assistant(Name('Alik', 'Akhmetov'), 2)
assistant.get_name()  # returns Name('Alik', 'Akhmetov')

Task 4

Implement __str__ methods in Name and Student.

print(name) # Daulet Kabdiyev Bolatovich
print(student) # Daulet Kabdieyv Bolatovich, student ID: 16BD02006
print(assistant) # Alik Akhmetov, studying 2 year

Task 4

Design a class PP2. PP2 has assistants which is a list of Assistant. PP2 also has students which is a list of Student. PP2 has groups which is dictionary where keys are strings and values are lists of Student. When PP2 is initialized, groups is empty.

• Implement method get_groups that returns a dictionary.
• Implement method get_assistants that returns a list of Assistant
• Implement method get_students that returns a list of Student

class PP2:

    def get_assistants():
        pass

    def get_students():
        pass

    def get_groups():
        pass

    def add_user_to_Group(name: Name, student: Student):
        pass

    def populate_from_csv(filename: str):
        pass

    def save_to_json(filename: str):
        pass

# example usage
pp2 = PP2([Assistant(Name('Alik', 'Akhmetov'), 2)], [Student('16BD02006', Name('Daulet', 'Kabdiyev', 'Bolatovich')), Student('16BD02007', Name('Ivan', 'Ivanov', 'Ivanovich'))])

pp2.get_groups() # returns empty dictionary, i.e. {}
pp2.get_students() # returns a list with 2 students: Daulet and Ivan
pp2.get_assistants() # returns a list with 1 assistant: Alik

Task 5

Implement method addUserToGroup(name: Name, student: Student) in PP2. name is assistant name. When student is added to group, student is added to assistant with given name. If no such assistant exists in groups, an empty list should be initialized and student added to it.

assistant1 = Assistant(Name('Alik', 'Akhmetov'), 2)
student1 = Student('16BD02006', Name('Daulet', 'Kabdiyev', 'Bolatovich'))
student2 = Student('16BD02007', Name('Ivan', 'Ivanov', 'Ivanovich'))

pp2 = PP2([assistant1], [student1, student2])

pp2.add_user_to_Group(assistant1.get_name(), student1)
pp2.add_user_to_Group(assistant1.get_name(), student2)

pp2.get_groups()

Task 6

Implement populate_from_csv method in PP2. Use CSV file provided by your assistant in Telegram group to populate pp2.

pp2 = PP2([], [])
pp2.populate_from_csv('pp2.csv') # populates pp2 with 84 students and 3 assistants, and adds all students to group according to assistants

Task 7

Implement save_to_json method in PP2. This methods dumps all data to JSON file that is saved in filename. All students and assistants are saved according to group affeliation

pp2.save_to_json('pp2.json') # saves all pp2 data to pp2.json file

Example contents of saved JSON file:

[
    {
        "Alik Akhmetov": [
            {
                "student_id": "16BD02006",
                "name": {
                    "first_name": "Daulet",
                    "last_name": "Kabdiyev",
                    "middle_name": "Bolatovich"
                }
            },
            {
                "student_id": "16BD02007",
                "name": {
                    "first_name": "Ivan",
                    "last_name": "Ivanov",
                    "middle_name": "Ivanovich"
                }
            }, 
            ... # other students from Alik Akhmetov's group
        ]
    }, 
    {
        "Darkhan Turgyn": [  #Darkhan Turgyn group's students ]
    },
    {
        "Bekbolat Ospan": [  #Bekbolat Ospan group's students ]
    }
]