Unit1-Understanding Algorithims

Multiple Choice

What is an algorithm?

• A way to do something

• A computer term that means a musical rhythm

• A list of steps

• Algorithm isn't a real word

Multiple Choice

Why is efficiency important in an algorithm?

• A) It ensures the algorithm gives accurate results

• B) It ensures the algorithm produces the same result each time

• C) It ensures the problem is solved in the shortest time with minimal resources

• D) It ensures the algorithm can replace a manual method

Multiple Choice

Which of the following best describes accuracy in an algorithm?

• A) Producing the same result every time it is run

• B) Solving the problem in the shortest possible time

• C) Leading to the expected outcome

• D) Using as many resources as possible

Multiple Choice

What does consistency mean in the context of algorithms?

• A) The algorithm must always produce the expected result, even with changes in input

• B) The algorithm must solve the problem faster than manual methods

• C) The algorithm must produce the same result each time it is run

• D) The algorithm must use as few computer resources as possible

Multiple Choice

What is the difference between an algorithm and a program?

• A) An algorithm is written in a programming language, a program is written in English

• B) An algorithm is a detailed design for a solution, a program is the implementation of that design

• C) An algorithm and a program are exactly the same

• D) A program designs a solution, and an algorithm executes it

Multiple Choice

A high-level programming language is a programming language that is similar to natural human language.

• True

• False

Multiple Choice

What is this symbol?

• Decision
• Input/Output
• Start/End
• Process

Multiple Choice

What is the correct symbol for an input in a flowchart?

• A parallelogram

• A rectangle

• A square

Multiple Choice

In a flowchart, which symbol is used to represent the start or end of an algorithm?

• A) Rectangle

• B) Diamond

• C) Oval (rounded rectangle)

• D) Parallelogram

Multiple Choice

What flowchart symbol does this represent?

• Input/Output
• Start/End
• Decision
• Process

Multiple Choice

Which flowchart symbol is used to represent a decision that needs to be made?

• A) Rectangle

• B) Diamond

• C) Oval

• D) Arrow

Multiple Choice

What does a parallelogram represent in a flowchart?

• A) Process to be carried out

• B) Logical flow of the algorithm

• C) Input or output

• D) Start or end of the algorithm

Multiple Choice

Why are computers considered useful when following algorithms?

• A) Because they can think and make their own decisions
  

• B) Because they follow instructions more quickly than humans

• C) Because they can design new algorithms themselves

• D) Because they do not require instructions to operate

Multiple Choice

What is the correct definition for 'pseudo code?'

• a notation resembling a complex programming language, used in program design.
• a notation resembling a simplified programming language, used in program design.

Multiple Choice

What is pseudocode?

• A simple java-like programming language

• Statements in plain English

• A control structure used in Java

• A java class

Multiple Choice

What is pseudocode?

• A) A high-level programming language

• B) A structured, code-like language used to describe an algorithm

• C) A type of flowchart symbol

• D) A compiled version of an algorithm

Multiple Choice

Why is pseudocode useful for a developer?

• A) It helps them focus on logic and efficiency without worrying about programming language rules

• B) It automatically converts into machine code

• C) It replaces the need for actual programming

• D) It eliminates the use of flowcharts

Multiple Choice

What makes pseudocode relatively straightforward?

• A) It uses natural human language only

• B) It can be easily translated into any high-level programming language

• C) It requires no understanding of logic

• D) It replaces the need for algorithms

Multiple Choice

What is a variable in programming?

• A) A fixed value that never changes

• B) A unique name given to a constant

• C) A container used to store data that can change during program execution

• D) A calculation performed on two numbers

Multiple Choice

What is an identifier?

• A calculation symbol used in arithmetic

• A descriptive name given to a variable or constant

• A container for storing values

• A character representing multiplication or division

Multiple Choice

What does an arithmetic operator do?

• A) Stores data in memory

• B) Describes something clearly

• C) Performs a calculation on two numbers

• D) Gives a variable a unique name

Multiple Choice

What is the result of 13 DIV 4?

• A) 3.25

• B) 3

• C) 1

• D) 27

Multiple Choice

Which operator is used to calculate the remainder of a division?

• MOD

• DIV

• ^

• –

Multiple Choice

The expression 3 ^ 3 is equal to:

• A) 6
  

• B) 9

• C) 27

• D) 81

Multiple Choice

What is the main difference between / and DIV?

• A) / gives the exact decimal result, while DIV gives only the whole number part

• B) / is used for subtraction, while DIV is used for division

• C) DIV can only be used with multiplication

• D) / gives the remainder, while DIV gives the power

Multiple Choice

What is the difference between a variable and a constant?

• A variable stores data that changes, while a constant stores data that does not change

• A variable stores numbers, while a constant stores text

• A variable is always larger than a constant

• A constant can change, while a variable cannot

Multiple Choice

Why should descriptive names be chosen for variables and constants?

• A) To make the program run faster

• B) To reduce the memory used

• C) To make the code easier to read and understand

• D) To prevent the program from crashing

Multiple Choice

Which of the following is an example of a naming convention in programming?

• A) Adding numbers at random in variable names

• B) Using camelCase or snake_case for identifiers

• C) Changing variable names halfway through a program

• D) Using one-letter names only

Multiple Choice

What is pseudocode?

• A) A precise method for solving a problem

• B) A structured, code-like language used to design algorithms

• C) The final program code written in a programming language

• D) A type of arithmetic operator

Multiple Choice

Why can’t a computer understand the instruction “Wait for water to boil” in an algorithm?

• A) Computers cannot perform repetitive tasks

• B) The instruction is ambiguous and lacks a clear measurable condition

• C) Computers do not have sensors for water

• D) The algorithm runs too quickly

Multiple Choice

What condition would make the algorithm clear for a computer to follow when boiling water?

• A) Wait until there is steam and bubbles

• B) Wait until the kettle turns off automatically

• C) Wait until the water reaches 100°C

• D) Wait until someone checks the kettle manually

Multiple Choice

Which construct in programming refers to a process being repeated until a condition is met?

• A) Selection

• B) Iteration

• C) Construct

• D) Condition

Multiple Choice

Which programming construct allows a choice to be made between different alternatives?

• A) Selection

• B) Iteration

• C) Construct

• D) Construct

Multiple Choice

In programming, what does iteration allow you to do?

• A) Make a choice between alternatives

• B) Store data that never changes

• C) Repeat the same set of statements several times

• D) Translate pseudocode into program code

Multiple Choice

Why are efficient searching algorithms important?

• A) They reduce the amount of RAM needed

• B) They allow information to be found quickly, even in very large lists

• C) They make data permanently stored

• D) They prevent algorithms from using loops

Multiple Choice

What happens in the bubble sort algorithm when two items are in the wrong order?

• A) They are deleted

• B) They are swapped

• C) They are skipped

• D) They are combined into one item

Multiple Choice

In the bubble sort algorithm (ascending order), what happens if two adjacent values are not in ascending order?

• A) The algorithm stops immediately

• B) The values are skipped and left in place

• C) The two values are swapped

• D) The values are deleted from the list

Multiple Choice

We are sorting the following list in ascending order:
 
1    4    2    9    3    8    5
 
What does the list look like after one pass of the bubble sort algorithm. 

• 1 2 4 3 8 5 9
• 1 4 2 5 3 8 9
• 4 2 9 3 8 5 1

Multiple Choice

What key technique does merge sort use to break down a problem into smaller parts?

• A) Iteration

• B) Parallel processing

• C) Recursion

• D) Selection

Multiple Choice

What does the graph show about the performance of Bubble Sort as the number of items increases?

• A) The time taken stays nearly constant

• B) The time taken increases rapidly

• C) The time taken decreases

• D) The time taken is always zero

Multiple Choice

According to the graph, which sorting algorithm is more efficient when the number of items becomes very large?

• A) Bubble Sort

• B) Merge Sort

• C) Both are equally efficient

• D) Neither — efficiency does not depend on the algorithm

Multiple Choice

Which of the following statements correctly describes the divide and conquer approach to solving the convex hull problem?

• The algorithm sorts the points and then adds them one by one to the convex hull using a greedy approach.

• The algorithm splits the set of points into two halves, recursively finds the convex hull for each half, and then merges the two convex hulls.

• The algorithm uses a stack to keep track of the vertices of the convex hull while scanning the points in sorted order.

• The algorithm starts with the leftmost point and sweeps to the rightmost point, adding points to the hull if they form a left turn.

Multiple Choice

Which algorithm design approach is Merge Sort based on?

• A) Brute force

• B) Divide and conquer

• C) Trial and error

• D) Sequential processing

Multiple Choice

In which situation might Bubble Sort be more practical than Merge Sort?

• A) When sorting very large datasets (over 100,000 items)

• B) When sorting lists smaller than 1000 items

• C) When maximum efficiency is always required

• D) When recursion cannot be used

Multiple Choice

Which statement best describes the divide and conquer algorithm design?

• It tries all possible solutions until one is found.

• It repeats the same task over and over again until it succeeds.

• It relies only on computer memory rather than processing power.

• It solves a problem by dividing it into smaller sub-problems and combining their solutions.

Multiple Choice

Which sorting algorithm works by repeatedly stepping through the list to be sorted, comparing each pair of adjacent items and swapping them if they are in the wrong order?

• Merge Sort

• Quick Sort

• Bubble Sort

• Insertion Sort

Multiple Choice

Which of the following sorting algorithms is considered a stable sort?

• Bubble Sort

• Quick Sort

• Heap Sort

• Selection Sort

Multiple Choice

What is the main characteristic of a linear search?

• A) It divides the list into two halves and searches each half.

• B) It always finds the item in a single step.

• C) It checks items one by one from the start until the item is found or the list ends.

• D) It rearranges the data into ascending order before searching.

Multiple Choice

Why is a linear search described as sequential?

• A) Because it splits the list into smaller sublists.

• B) Because it only works on sorted data.

• C) Because it skips every other item while searching.

• D) Because it goes through the list item by item in order.

Multiple Choice

What is a key requirement for using a binary search?

• A) The list must be sorted in ascending or descending order.

• B) The list must contain only unique numbers.

• C) The list must always start with the number 0.

• D) The list must be arranged in pairs.

Multiple Choice

In a binary search, when there is an even number of items in the list, which number is chosen as the median?

• A) The lower of the two middle numbers

• B) The average of the two middle numbers

• C) The higher of the two middle numbers

• D) A randomly chosen middle number

Multiple Choice

How can the efficiency of searching algorithms be compared?

• A) By counting how many steps the programmer writes

• B) By checking whether the algorithm uses recursion

• C) By measuring the clock speed of the CPU

• D) By analyzing the ‘best case’ and the ‘worst case’ scenarios

Multiple Choice

A linear search is always more efficient than a binary search.

• True

• False

Multiple Choice

In the best-case scenario for a binary search of 1000 items, how many comparisons are required?

• 1

• 5

• 10

• 1000

Multiple Choice

In the worst-case scenario for a binary search of 1000 items, how many comparisons are required?

• 1

• 5

• 10

• 1000

Multiple Choice

What is the main disadvantage of using a binary search algorithm?

• A) It is slower than a linear search

• B) It requires the list to be sorted first

• C) It cannot handle large lists

• D) It only works with text data

Multiple Choice

What is the main advantage of using binary search over linear search?

• It is easier to implement.

• It works on unsorted arrays.

• It has a faster average time complexity.

• It requires less memory.

Multiple Choice

Which of the following is a necessary condition for binary search to work?

• The list must contain only integers.

• The list must be sorted.

• The list must be in descending order.

• The list must have an even number of elements.

Multiple Choice

In a binary search, if the target value is greater than the middle element, what is the next step?

• Search the left half of the list.

• Search the right half of the list.

• Return the middle element.

• Search the entire list again.

Multiple Choice

Which of the following best describes the binary search algorithm?

• It searches for an element by checking each one sequentially.

• It uses a divide and conquer approach.

• It uses a breadth-first search.

• It uses a depth-first search.

Multiple Choice

The mechanism of finding an element /key in a given set of elements is known as ________________

• sorting

• searching

• both

• none

Multiple Choice

What is the main factor in deciding which sorting or searching algorithm to use?

• The brand of the computer being used

• The size and nature of the data to be processed

• The color scheme of the programming environment

• The programming language used

Multiple Choice

What would the average number of iterations be for the Linear Search Algorithm, where n represents number of elements?

• n

• n/2

• n^2

• n-1

Multiple Choice

Identify the INCORRECT statement about searching

i. Binary search starts by testing the largest data

ii. Linear search can be done for unsorted data only

iii. Linear search starts by testing data at the middle of list

iv. Binary search can be done for sorted homogeneous data

• i, ii and iii

• ii, iii and iv

• i, iii and iv

• i, ii, iii and iv

Multiple Choice

Which of these is NOT a Sort algorithm

• Binary
• Merge
• Bubble
• Insertion

Multiple Choice

What are decomposition and abstraction examples of in computational thinking?

• a) Thought processes

• b) Hardware components

• c) Programming languages

• d) Sorting algorithms

Multiple Choice

Which of the following is an example of thinking computationally?

• Planning out your route when going to meet a friend
• When going to meet a friend, wandering around until you find them
• When going to meet a friend, asking a parent to plan your route for you

Multiple Choice

Breaking a complex problem down into smaller problems and solving each one individually.

• Decomposition
• Abstraction
• Programming
• Algorithmic Thinking

Multiple Choice

Q: In computational thinking, what does decomposition involve?

• a) Writing algorithms in pseudocode

• b) Removing unnecessary details to focus on the main points

• c) Breaking a problem into smaller, more manageable parts

• d) Testing a program to ensure it works correctly

Multiple Choice

What is one main advantage of using decomposition in problem solving?

• a) It removes unnecessary details from a problem

• b) It allows sub-problems to be solved by different teams simultaneously

• c) It guarantees that no errors will occur in the final program

• d) It makes the program run faster on the computer

Multiple Choice

What is one benefit of decomposition when algorithms are turned into programs?

• a) It ensures the program will never crash

• b) It increases the speed of the processor

• c) It reduces the need for testing

• d) It allows code to be reused in future programs

Multiple Choice

What does abstraction mean in computer science?

• a) Removing unnecessary details and focusing only on the essential features

• b) Writing an algorithm step by step in detail

• c) Repeating a set of instructions until a condition is met

• d) Breaking a problem into smaller, more manageable parts

Multiple Choice

Which of the following best illustrates the concept of abstraction?

• a) A programmer writing every single machine instruction for a program

• b) A driver fixing the engine before starting the car

• c) A programmer using the print command without knowing how it works internally

• d) A mechanic describing every spark and fuel process to a driver before they drive

Multiple Choice

Why do high-level programming languages require a translator before execution?

• a) Because they are already written in binary code (1s and 0s)

• b) Because they can only be used to design games like noughts and crosses

• c) Because they directly match the processor’s instruction set

• d) Because the processor cannot understand them without translation into binary

Multiple Choice

What is the main purpose of using subprograms in programming?

• a) To reduce program complexity and make code easier to understand

• b) To replace the need for the main program

• c) To store binary instructions permanently

• d) To increase the processor’s clock speed

Multiple Choice

When designing a solution to a problem, what should be identified at the outset?

• a) The hardware specifications of the computer

• b) The color and appearance of the user interface

• c) The inputs, outputs, and processing requirements

• d) The order in which users will test the program