2026 · Paper 1

Complete GATE DA 2026 Paper 1 overview, original pages and practice · Timed previous-paper practice

Questions 40–42 of 65. Imported answers require review unless explicitly marked reviewed.

Question 40

Open question

DAMCQ2 marksNeeds review

Consider a directed graph



, where



is the finite set of vertices and



is the set of directed edges between the vertices.



may contain cycles but there is no self-loop. Further,



may not be strongly connected.

Let



be the graph obtained by reversing the directions of all the edges in



without changing the set of vertices.

Assume that Breadth First Search (BFS) or Depth First Search (DFS) from any given vertex



of a graph visits only the reachable vertices from



in that graph.

Which of the following statements must always be true, regardless of the structure of



?

Your answerChoose one option.

A.

If



is a reachable vertex in the BFS of



from



, then



is also a reachable vertex in the DFS of



from



.

B.

In



, the BFS traversal from



will visit exactly the same set of vertices as the DFS from



in



.

C.

The order of vertices visited in the BFS of



from



is the reverse of the order of vertices visited in the DFS of



from



.

D.

If



is a reachable vertex in the DFS of



from



, then



is also a reachable vertex in the BFS of



from



.

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Question 41

Open question

DAMCQ2 marksNeeds review

Consider a B+ Tree where the maximum number of key values in each leaf node is 2 and the maximum number of pointers in each non-leaf node is 3. Let the content of the B+ Tree be as shown in the figure.

Which of the following options denotes the key value(s) stored in the root node after inserting a key value 3 in the given B+ Tree?



Your answerChoose one option.

A.

5

B.

8

C.

3 and 5

D.

3, 5 and 8

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Question 42

Open question

DAMCQ2 marksNeeds review

Consider the given relations



,



and



. The relation



has three columns



,



and



. The relation



has three columns



,



and



. The relation



has two columns



and



.

Relation



:

		
P1	Q1	R1
P2	Q2	R2
P3	Q3	R2

Relation



:

		
P1	Q1	2
P1	Q2	5
P2	Q1	6
P3	Q3	1

Relation



:

	
P1	T1
P3	T2
P4	T3
P4	NULL

Consider the relational algebra expression



where



denotes natural join operation.

Which of the following options is the correct output for the given expression?

Your answerChoose one option.

A.

Two rows (P1, R1, 2) and (P1, R1, 5)

B.

Three rows (P1, R1, 2), (P1, R1, 5) and (P2, R2, 6)

C.

One row (P1, R1, 2)

D.

Zero rows

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