Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions for Computer Science (Python)

Write the use and syntax for the following method:

open()

Write a command(s) to write the following lines to the text file named hello.txt. Assume that the file is opened in append mode.

“ Welcome my class”
“It is a fun place”
“You will learn and play”

Write a Python program to open the file hello.txt used below in read mode to display its contents. What will be the difference if the file was opened in write mode instead of append mode?

“ Welcome my class”
“It is a fun place”
“You will learn and play”

Write a program to accept string/sentences from the user till the user enters “END” to. Save the data in a text file and then display only those sentences which begin with an uppercase alphabet.

State TRUE or FALSE for the following case:

In POSTFIX notation for expression, operators are placed after operands.

For the following arithmetic expression:

((2+3)*(4/2))+2

Show step-by-step process for matching parentheses using stack data structure.

Evaluate following postfix expression while showing status of stack after the operation given A = 3, B = 5, C = 1, D = 4.

A B + C *

Evaluate following postfix expressions while showing status of stack after the operation given A = 3, B = 5, C = 1, D = 4.

A B * C / D *

How is queue data type different from deque data type?

Deletion of elements is performed from ______ end of the queue.

______ is a data structure where elements can be added or removed at either end, but not in the middle.

A deque contains ‘z’, ’x’, ’c’, ’v’ and ‘b’. Elements received after deletion are ‘z’, ’b’, ’v’, ’x’ and ‘c’. ______ is the sequence of deletion operation performed on deque.

Write a python program to check whether the given string is palindrome or not, using deque. (Hint : refer to algorithm 4.1)

Consider the following lists:

List 1:

List 2: 

If the lists are sorted using Insertion sort then which of the lists List1 or List 2 will make the minimum number of comparisons? Justify using diagrammatic representation.

During admission in a course, the names of the students are inserted in ascending order. Thus, performing the sorting operation at the time of inserting elements in a list. Identify the type of sorting technique being used and write a program using a user defined function that is invoked every time a name is input and stores the name in ascending order of names in the list.

Use the hash function: h(element) = element%11 to store the collection of numbers: [44, 121, 55, 33, 110, 77, 22, 66] in a hash table. Display the hash table created. Search if the values 11, 44, 88, and 121 are present in the hash table, and display the search results.

Write a Python program by considering a mapping of the list of countries and their capital cities such as:

CountryCapital= {'India':'New Delhi','UK':
                             'London','France':'Paris',
                             'Switzerland': 'Berne',
                             'Australia': 'Canberra'}

Let us presume that our hash function is the length of the Country Name. Take two lists of appropriate size: one for keys (Country) and one for values (Capital). To put an element in the hash table, compute its hash code by counting the number of characters in the Country, then put the key and value in both lists at the corresponding indices. For example, India has a hash code of 5. So, we store India at the 5th position (index 4) in the keys list, New Delhi at the 5th position (index 4) in the values list, and so on. So that we end up with:

Now search the capital of India, France, and the USA in the hash table and display your result.

A bank ‘xyz’ wants to know about its popularity among the residents of a city ‘ABC’ on the basis of the number of bank accounts each family has and the average monthly account balance of each person. Briefly describe the steps to be taken for collecting data and what results can be checked through the processing of the collected data.

Identify the type of data being collected/generated in the following scenario:

Recording a video.

Identify the type of data being collected/generated in the following scenario:

Marking attendance by the teacher.