Data Structures MCQ Quiz in मल्याळम - Objective Question with Answer for Data Structures - സൗജന്യ PDF ഡൗൺലോഡ് ചെയ്യുക

The correct answer is option  3.

Concept:

The given python snippet is,

import collections
dq = collections.deque([1, 2, 3])
dq.append(5)
dq.appendleft(6)
dq.extend([7])
print(list(dq))

Explanation:

Here dq is the deque. We can insert or delete from both ends. 

dq = collections.deque([1, 2, 3])

A deque has three elements 1, 2, 3.

dq.append(5)
The append function inserts the elements at end of the list. The deque has 1, 2, 3, and 5.

dq.appendleft(6)
The append left function inserts the elements at end of the left list. The deque has 6, 1, 2, 3, and 5.

dq.extend([7])
Extend function insert the list of elements to the existing list. The deque has 6, 1, 2, 3, 5, and 7.

Hence the correct answer is [6, 1, 2, 3, 5, 7]

The correct answer is option 3.

Concept:

Queues:

• The queue is an abstract data structure, somewhat similar to Stacks.
• Unlike stacks, a queue is open at both ends. One end is always used to insert data (en queue) and the other is used to remove data (de queue). Queue follows the First-In-First-Out methodology, i.e., the data item stored first will be accessed first.
• Queue follows the principle of First In First Out (FIFO) and Last In Last Out (LILO)

maxsize:

The maximum number of items in the queue. 

put(item): 

Add something to the queue. Wait until a free spot becomes available if the queue is filled before adding the item. 

qsize(): 

Return the number of items in the queue.

full():

If there are maxsize items in the queue, return True. 

get():

A queue item can be removed and returned. Wait until an item is available if the queue is empty.

empty():

Return True if the queue is empty, False otherwise. Here queue is not empty because the still elements are there in the queue. Example:

Explanation:

from queue import Queue
q=Queue(maxsize=10)

q.put('A')
q.put('AA')
q.put('AAA')

print(q.qsize())

print(q.full())
print(q.get())

print(q.empty())

Hence the correct answer is empty().

The correct answer is option 1.

Concept:

A deque is a two-ended queue in which elements can be inserted and deleted from either the left or right end. The collections module in Python has a deque implementation.

reverse():

Reverse the order of the deque.

Explanation:

The given data,

import collections
dq = collections.deque([4, 5, 6,7,8])

Here the deque has 4, 5, 6, 7, 8.
dq.reverse()

The reverse function is the order of the deque. The deque has [8, 7, 6, 5, 4]
print(list(dq))

The deque prints [8, 7, 6, 5, 4].

Hence the correct answer is [8, 7, 6, 5, 4].

The correct option is Midfix

CONCEPT:

There are mainly three notations used for writing expression:

Infix notation: When the operator is written in between the operands it is known as infix notation. Example 2+5

Prefix notation: When the operator is written before the operands it is known as Prefix notation. Example +25

Postfix notation: When the operator is written after the operands it is known as Postfix notation. Example 25+

But there is no notation like Midfix to represent an expression.

The correct answer is option 3.

Concept:

Stack:

A Stack is a data structure that is linear. It uses the Last In, First Out (LIFO) storage mechanism. A new element is always added to the top of a stack when it is added, and the top element is always removed first from a stack.

Explanation:

The given code is,

a = []
a.append('1')
a.append('2')
a.pop()
a.append('3')
a.append('4')
print(a)

It follows the below figure manner.

Hence the correct answer is ['1', '3', '4 '].

The de queue is a combination of both queue and stack,  where we can push and pop from both left and right sides. So, it can be used as both stack and queue, 

In stack, we use to insert in the front, and in the queue, we used to insert from the back. So, both work we can do on de queue, That's why it's called as Double Ended queue.
dequeue allows you to efficiently add or remove the item from Either end of the list. 
So, the Assertion statement is correct. 

Now, the reason is also true and correctly explains the assertion. In the de queue, we can insert and delete from both the ends that's why it can support both stack and queue.

de queue is implemented as a double-linked list in the system and we can insert and delete from both ends.

So, option 3 turns out to be the correct answer as Reason correctly explains the Assertion.  

The correct answer is option 3.

Concept:

Statement 1: A single deque can support both stack and queue operations.

True, The word deque, usually pronounced deck, is short for double-ended queue. A deque is a list that supports insertion and removal at both ends. Thus, a deque can be used as a queue or as a stack.

• A deque elements insertion and deletion are done from only one end so it follows the stack property(First in Last out).
• A deque elements insertions are done from only one end and deletion is done from another end. so it follows the queue property(Last in first out).

Statement 2: A single stack can support both deque and queue operations.

False, A stack can not supports the deque and queue operations because it has the restriction that insertion and deletion are done from only one end.

Statement 3: A single queue can support both stack and queue operations.

False, A queue can not supports the deque operations because it has the restriction that insertion on one end and deletion is done from another end. 

Hence the correct answer is only statement 2 and statement 3.

The correct option is 33

CONCEPT:

Stack is a data structure that follows last in first out order for insertion and deletion of items.

The insertion and deletion of items take place from one end only using the top pointer.

EXPLANATION:

In the above program, the following operations are performed on the stack "s"  before executing the for loop

push(15), push(5), pop(), push(7), push(11)

Now items of the stack are popped one by one in the while loop and added to the sum variable 

#iteration 1 : sum = sum + s.pop() = 0 + 11

#iteration 2 : sum = sum + s.pop() = 11 + 7

#iteration 3 : sum = sum + s.pop() = 18 + 15

after popping 3 items from the stack, the stack becomes empty and the while loop stops/ends.

The final value of sum = 33 that will be printed in the end.

Correct option is stackone = list()

CONCEPT:

Lists in Python can be created using list() method or by placing the values inside square brackets[], for example

a=[1,2,3] 

or we can create list using list() method and then add elements using append() method

a=list()

a.append(1)

a.append(2)

a.append(3)

 

In the above question

Option 2 stackone != list() 

/ here not-equal-to operator is used which is a comparision operator. 

Option 3 stackone = list[]

/ invalid syntax list[]

Option 4 stackone = stacklist() 

/  error as there is no method named stacklist() 

Queue is a data structure which follows FIFO pattern ( first in first out) means the element which inserted first should come out first. 
In queue , enqueue means inserting an element and dequeue means deleting an element from the queue. 

Remember , delete should happen from the front and insert should happen from back ( rear ) side.

So, To implement the enqueue operation , we need to first check the queue is full or not, for that we use isfull() function , which returns a binary value - either true or false .
 
To implement dequeue operation we need to first check if element present in the queue or not, for that we need isempty() function , if the function returns false that means queue have at least 1 element and we can delete that. 

peek() function used to return the front element of the queue , as deletion happens from the front , so, we need peek operation to find out the front element.
So, option 3 will be the correct answer .

Why option 1 and 2 got eliminated - 
we need 3 operation ( isempty,isfull,peek ) combine for the operation , and the options does not satisfy that . 

why option 4 got eliminated - 
insertrear() function used to insert an element in the rear position , but here , in this question , we do not require that.