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Past Questions
Which of the following is not a type of constructor?
A)
Copy constructor
B)
Friend constructor
C)
Default constructor
D)
Parameterized constructor
In Object-Oriented Programming (specifically in C++), a constructor is a special member function that is automatically called when an object of a class is created.
1. **Default Constructor (Option c):** A constructor that accepts no arguments. If no constructor is defined, the compiler provides one automatically.
2. **Parameterized Constructor (Option d):** A constructor that accepts arguments to initialize an object with specific values.
3. **Copy Constructor (Option a):** A constructor used to create a new object as a copy of an existing object of the same class.
**Why 'Friend constructor' is incorrect:** In C++, a 'friend' is a keyword used to grant a non-member function or another class access to the private and protected members of a class. While you can have 'friend functions' or 'friend classes', there is no such concept as a 'friend constructor'. A constructor must be a member of the class it initializes; it cannot be a 'friend' because its primary purpose is to initialize the internal state of the object from within the class scope.
What is true about a class and a structure?
A)
A class contains both variables and functions but a structure can contain variables only.
B)
The data items inside a structure are private by default but inside a class pubic by default.
C)
A class and structure are not similar at all.
D)
None of the above
To determine the correct answer, we must analyze the properties of classes and structures, specifically in the context of C++ (where both exist and are most frequently compared in CSE exams):
1. Analysis of Option (a): 'A class contains both variables and functions but a structure can contain variables only.' This is FALSE. In C++, a `struct` is almost identical to a `class`; it can contain both member variables (data members) and member functions (methods).
2. Analysis of Option (b): 'The data items inside a structure are private by default but inside a class public by default.' This is FALSE. It is actually the opposite: in a `struct`, members are **public** by default, whereas in a `class`, members are **private** by default.
3. Analysis of Option (c): 'A class and structure are not similar at all.' This is FALSE. They are very similar; the primary difference is the default access specifier (public for struct, private for class).
Since options (a), (b), and (c) are all technically incorrect, the correct choice is (d) None of the above.
Which of the following operator is used by catch-all handlers?
A)
Ternary operator
B)
Ellipses operator
C)
String operator
D)
Unary operator
In Object-Oriented Programming (specifically in C++), a 'catch-all handler' is a special type of exception handler that can catch any type of exception thrown, regardless of its data type. This is achieved using the ellipses operator '...', which consists of three dots.
Example:
catch(...) {
// This block handles any exception thrown
}
Why other options are incorrect:
- a. Ternary operator: This is a conditional operator (?:) used as a shorthand for if-else statements.
- c. String operator: There is no single 'string operator'; strings are handled via operators like '+' for concatenation in many languages.
- d. Unary operator: These are operators that act on a single operand (e.g., ++, --, !), which have no relation to exception handling mechanisms.
Consider the following page reference string: 1 2 3 4 2 1 5 6 2 1 2 3 7 6 3 2 1 2 3 6. For LRU page replacement algorithm with 5 frames, the number of page faults is?
A)
10
B)
14
C)
8
D)
11
Based on established principles in Basic Computer Knowledge, the correct and most appropriate choice is '8' (Option C).
Which key do you need to press in order to access the system boot menu?
A)
F4
B)
F7
C)
F8
D)
F5
In the context of traditional PC hardware and legacy BIOS/Windows environments (which are typically the basis for these technical competitive exams), the F8 key is the standard key used to access the Advanced Boot Options menu (Safe Mode, Last Known Good Configuration, etc.) during the system startup process. While modern UEFI systems and Windows 10/11 have moved toward software-based recovery menus, F8 remains the textbook answer for 'system boot menu' in computer hardware fundamentals.
Breakdown of other options:
- F4: Generally used for application-specific shortcuts or system recovery in some specific OEM brands, but not a universal boot menu key.
- F7: Often used for 'Advanced Startup' in some specific laptop brands or for spell-check in software, but not the standard boot menu key.
- F5: Often used for refreshing pages or specific diagnostic tools in some BIOS versions, but not the primary boot menu key.
Given two points P (3, 2) and Q (2, 6) in the coordinate plane, find out the equation of the line passing through both points.
A)
-4x + 1y = -14
B)
4x - 1y = -14
C)
4x + 1y = 14
D)
-4x - 1y = 14
To find the equation of the line passing through points P(3, 2) and Q(2, 6), we follow these steps:
1. **Calculate the Slope (m):**
The formula for the slope is m = (y2 - y1) / (x2 - x1).
m = (6 - 2) / (2 - 3) = 4 / (-1) = -4.
2. **Use the Point-Slope Form:**
The equation of a line is y - y1 = m(x - x1). Using point P(3, 2):
y - 2 = -4(x - 3)
y - 2 = -4x + 12
3. **Convert to Standard Form (Ax + By = C):**
Rearrange the equation to bring x and y to one side:
4x + y = 12 + 2
4x + 1y = 14
**Verification of Options:**
- Option (a): -4x + 1y = -14. If x=3, y=2: -4(3) + 2 = -10 (Incorrect).
- Option (b): 4x - 1y = -14. If x=3, y=2: 4(3) - 2 = 10 (Incorrect).
- Option (c): 4x + 1y = 14. If x=3, y=2: 4(3) + 2 = 14 (Correct). If x=2, y=6: 4(2) + 6 = 14 (Correct).
- Option (d): -4x - 1y = 14. If x=3, y=2: -4(3) - 2 = -14 (Incorrect).
Which option represents an instance of a Real Time Operating System?
A)
MAC
B)
MS-DOS
C)
Windows 10
D)
Process Control
A Real-Time Operating System (RTOS) is designed to process data and respond to events within a strict, predefined time constraint (deadline).
1. **Option d (Process Control):** In industrial automation and engineering, 'Process Control' systems (such as those used in chemical plants, robotics, or aircraft control) require deterministic behavior where a failure to respond within a specific timeframe could lead to system failure or catastrophe. These are the primary use cases for RTOS.
2. **Option a (MAC):** macOS is a General Purpose Operating System (GPOS) designed for user experience, multitasking, and versatility, not for strict real-time guarantees.
3. **Option b (MS-DOS):** MS-DOS is a single-tasking, command-line operating system. While it is simple, it is not a real-time system designed for deterministic scheduling.
4. **Option c (Windows 10):** Windows 10 is a GPOS. While it can be modified with real-time extensions, the standard version prioritizes throughput and fairness over strict timing deadlines.
Therefore, 'Process Control' is the only option that represents a functional instance/application of a Real-Time Operating System.
Which of these is false for Boundary-fill algorithm?
A)
Recursive algorithm
B)
Begins with a starting point called seed
C)
It checks for any pixel to be boundary color
D)
Works only for rectangles and circles
The Boundary-fill algorithm is a general-purpose area-filling algorithm used in computer graphics to fill an arbitrarily shaped region. Here is the evaluation of the options:
1. **Option (a) Recursive algorithm**: This is TRUE. The boundary-fill algorithm typically uses a recursive approach (either 4-connected or 8-connected) to visit neighboring pixels and fill them until a boundary color is encountered.
2. **Option (b) Begins with a starting point called seed**: This is TRUE. The algorithm requires an initial interior point, known as the 'seed point', to start the filling process.
3. **Option (c) It checks for any pixel to be boundary color**: This is TRUE. The core logic of the algorithm is to check if the current pixel is neither the boundary color nor already the fill color; if so, it fills the pixel and recurses to its neighbors.
4. **Option (d) Works only for rectangles and circles**: This is FALSE. The boundary-fill algorithm is designed to work for any closed shape defined by a specific boundary color, regardless of whether it is a simple geometric shape (like a circle) or a complex, irregular polygon.
Since the question asks for the FALSE statement, option (d) is the correct answer.
What does an operating system do
A)
An interface that regulates hardware and software programs
B)
A hardware device
C)
A program that operates the hardware devices
D)
A program that operates the software devices
An Operating System (OS) is a system software that acts as an intermediary or interface between the computer user/application software and the computer hardware. Its primary roles include resource management (CPU, memory, I/O devices) and providing a platform for application software to run.
Analysis of options:
- Option (a) is correct because the OS regulates how software programs access hardware resources, ensuring efficiency and preventing conflicts.
- Option (b) is incorrect because an OS is software, not a physical hardware device.
- Option (c) is partially true in a narrow sense, but 'operates the hardware devices' is an incomplete description; the OS manages them rather than just 'operating' them, and it must also manage software.
- Option (d) is incorrect because 'software devices' is a technically inaccurate term; software consists of programs and data, not 'devices'.
A process executes the code: fork(); fork(); fork(); fork(); The total number of child processes created is
A)
10
B)
9
C)
7
D)
8
Based on established principles in Basic Computer Knowledge, the correct and most appropriate choice is '8' (Option D).
Consider raster systems with resolutions, 2560 × 1024, What size frame buffer (in Kilo bytes) is needed for each of these systems to store 32 bits per pixel?
A)
10240 KB
B)
5120KB
C)
3840 KB
D)
20480 KB
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is '5120KB' (Option B).
If we want to resize a 1024 × 768 pixels image to one that is 720 pixels wide with the same aspect ratio, what would be the height of the resized image?
A)
420 Pixels
B)
460 Pixels
C)
480 Pixels
D)
540 Pixels
To maintain the aspect ratio of an image during resizing, the ratio of the width to the height must remain constant.
1. **Identify the original dimensions:**
Original Width ($W_1$) = 1024 pixels
Original Height ($H_1$) = 768 pixels
2. **Calculate the Aspect Ratio:**
Aspect Ratio = $W_1 / H_1 = 1024 / 768$
Simplifying the fraction: $1024 / 768 = 4 / 3$ (or approximately 1.333)
3. **Set up the equation for the resized image:**
Let the new width ($W_2$) = 720 pixels
Let the new height be $H_2$
Since the aspect ratio is the same: $W_1 / H_1 = W_2 / H_2$
$1024 / 768 = 720 / H_2$
4. **Solve for $H_2$:**
$H_2 = (720 \times 768) / 1024$
$H_2 = 552960 / 1024$
$H_2 = 540$
Therefore, the height of the resized image is 540 pixels.
Comparing this to the options:
- a. 420 Pixels: Incorrect
- b. 460 Pixels: Incorrect
- c. 480 Pixels: Incorrect
- d. 540 Pixels: Correct
Power set of empty or Null set has exactly ________ subset.
A)
One
B)
Three
C)
Two
D)
Zero
Based on established principles in Quantitative Aptitude, the correct and most appropriate choice is 'Zero' (Option D).
Which one of the following in NOT necessarily a property of a Group?
A)
Commutativity
B)
Associativity
C)
Existence of inverse for every element
D)
Existence of identity
Based on established principles in Quantitative Aptitude, the correct and most appropriate choice is 'Commutativity' (Option A).
If the clock input applied to a cascaded Mod-6 & Mod-4 counter is 48KHz. Than the output of the cascaded arrangement shall be of
A)
8 KHz
B)
12 KHz
C)
2 KHz
D)
18 KHz
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is '8 KHz' (Option A).
________ is suitable for testing the odd parity of word.
A)
AND gate
B)
OR gate
C)
NOR gate
D)
XOR gate
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'AND gate' (Option A).
Select the Number of ripple counter in IC ________ are
A)
7492
B)
7865
C)
7493
D)
7654
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is '7493' (Option C).
Which of the architecture is power efficient?
A)
RISC
B)
ISA
C)
IANA
D)
CISC
Based on established principles in the relevant subject area, the correct and most appropriate choice is 'ISA' (Option B).
Assume a binary search tree is constructed using the integer values and searched for the number 55. Identify the INCORRECT sequence from the list given. Justify your answer.
A)
10, 75, 64, 43, 60, 57, 55
B)
90, 12, 68, 34, 62, 45, 55
C)
9, 85, 47, 68, 43, 57, 55
D)
79, 14, 72, 56, 16, 53, 55
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is '90, 12, 68, 34, 62, 45, 55' (Option B).
The best average behaviour is shown by
A)
Merge Sort
B)
Insertion Sort
C)
Quick Sort
D)
Heap Sort
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'Quick Sort' (Option C).
Recursive algorithms are based on
A)
Divide and conquer approach
B)
Top-down approach
C)
Bottom-up approach
D)
Hierarchical approach
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'Top-down approach' (Option B).
Each process is represented in the OS by a
A)
system task control block
B)
operating system control block
C)
system control block.
D)
process control block
Based on established principles in Basic Computer Knowledge, the correct and most appropriate choice is 'system control block.' (Option C).
Let S be a set of n elements. The number of ordered pairs in the largest and the smallest equivalence relations on S is
A)
n and n
B)
n2 and n
C)
n2 and 0
D)
n and 1
Based on established principles in Quantitative Aptitude, the correct and most appropriate choice is 'n and 1' (Option D).
Where is the logic set when the transmission line is idle in the asynchronous transmission?
A)
Remains in the previous state
B)
It is set to logic low
C)
It is set to logic high
D)
State of the transmission line is not used to start transmission
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'State of the transmission line is not used to start transmission' (Option D).
Consider the binary relation R = {(x, y), (x, z), (z, x), (z, y)} on the set {x, y, z}. Which one of the following is TRUE?
A)
R is symmetric but NOT antisymmetric
B)
R is NOT symmetric but antisymmetric
C)
R is both symmetric and antisymmetric
D)
R is neither symmetric nor antisymmetric
Based on established principles in Quantitative Aptitude, the correct and most appropriate choice is 'R is neither symmetric nor antisymmetric' (Option D).