Computer Science and Information Technology
GATE CSE format:nat PYQs
Build your understanding with focused practice from past exam papers.
Questions 221–230 of 281. Imported answers require independent review unless marked reviewed.
Question 18
Open questionCSNAT1 markNeeds review
The chromatic number of the following graph is ______.

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Open questionCSNAT1 markNeeds review
Let G be a finite group on 84 elements. The size of a largest possible proper subgroup of G is ______.
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Open questionCSNAT1 markNeeds review
The postorder traversal of a binary tree is 8,9,6,7,4,5,2,3,1. The inorder traversal of the same tree is 8,6,9,4,7,2,5,1,3. The height of a tree is the length of the longest path from the root to any leaf. The height of the binary tree above is ____.
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Open questionCSNAT1 markNeeds review
Consider the following C program:
#include <stdio.h>
int counter = 0;
int calc (int a, int b) {
int c;
counter++;
if (b==3) return (a*a*a);
else {
c = calc(a, b/3);
return (c*c*c);
}
}
int main () {
calc(4, 81);
printf("%d", counter);
}
The output of this program is ____.
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Open questionCSNAT1 markNeeds review
Consider the sequential circuit shown in the figure, where both flip-flops used are positive edge-triggered D flip-flops.

The number of states in the state transition diagram of this circuit that have a transition back to the same state on some value of “in” is ____.
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Open questionCSNAT1 markNeeds review
A 32-bit wide main memory unit with a capacity of 1 GB is built using 256 M × 4-bit DRAM chips. The number of rows of memory cells in the DRAM chip is
. The time taken to perform one refresh operation is 50 nanoseconds. The refresh period is 2 milliseconds. The percentage (rounded to the closest integer) of the time available for performing the memory read/write operations in the main memory unit is ________.Log in to check the answer
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Open questionCSNAT1 markNeeds review
Consider a system with 3 processes that share 4 instances of the same resource type. Each process can request a maximum of K instances. Resource instances can be requested and released only one at a time. The largest value of K that will always avoid deadlock is ____.
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Open questionCSNAT1 markNeeds review
Consider a long-lived TCP session with an end-to-end bandwidth of 1 Gbps (=
bits-per-second). The session starts with a sequence number of 1234. The minimum time (in seconds, rounded to the closest integer) before this sequence number can be used again is ________.Log in to check the answer
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Open questionCSNAT2 marksNeeds review
Let G be a graph with
vertices, with each vertex labelled by a distinct permutation of the numbers 1, 2, ..., 100. There is an edge between vertices
and
if and only if the label of
can be obtained by swapping two adjacent numbers in the label of
. Let y denote the degree of a vertex in G, and z denote the number of connected components in G. Then,
_____.Log in to check the answer
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Open questionCSNAT2 marksNeeds review
Consider Guahati (G) and Delhi (D) whose temperatures can be classified as high (H), medium (M) and low (L). Let
denote the probability that Guahati has high temperature. Similarly,
and
denote the probability of Guahati having medium and low temperatures respectively. Similarly, we use
,
and
for Delhi.The following table gives the conditional probabilities for Delhi’s temperature given Guwahati’s temperature.
| | | |
|---|---|---|---|
| 0.40 | 0.48 | 0.12 |
| 0.10 | 0.65 | 0.25 |
| 0.01 | 0.50 | 0.49 |
Consider the first row in the table above. The first entry denotes that if Guwahati has high temperature (
) then the probability of Delhi also having a high temperature (
) is 0.40; i.e.,
. Similarly, the next two entries are
and
. Similarly for the other rows.If it is known that
,
, and
, then the probability (correct to two decimal places) that Guwahati has high temperature given that Delhi has high temperature is _____.Log in to check the answer
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