CH 1 - PROBLEM SOLVING (Module 1)

Question 1

5 steps of problem solvin cycle

Answer 1

1. analyzin the problem
   i. understand the problem well
   ii. amalyze the problem
2. developin an alorithm
   i. think of possible solutions
   ii. follow a modular approavh
   iii. identify operations for solutions
3. codin
   i. code program using appropriate control structures
4. testin and debuin
   i. test and debu
   ii. complete your documentation
5. maintaining and implementin
   i. implement your code
   ii. maintain your proram

Question 2

what is codin

Answer 2

codin is the technical word fro writin a proram. thji step is to translate the aloritm into a prora,min lanuae

Question 3

testin

Answer 3

estin is the process of findin errors in the proram

Question 4

debuin

Answer 4

the process of correctin errors found durin the testin process

Question 5

documentation

Answer 5

it is intended to allow another person or prorammer to understand the proram at a later date
miht also conain a adetrailedx description of what the proram does and how to use the proram

Question 6

maintainin a aproram

Answer 6

involves modifiyin the prorams to emove previuouly undetected errors, to enhance the proram with different features or functionality, keepin the proram up to date with ivernment reukationso rcompany policies

Question 7

decomposition

Answer 7

the process of breakin down a bi or complex problems into a set of smaller sub processes to allow us to describe, understand or execute the problem better
2. breakin a lare problem into more manaeable sub problems

Question 8

what does decomposition involve

Answer 8

1. dividin a task into a sequence of subtasks

2. identifyin elemts or parts of a complex system

Question 9

what is the need of decomposition

Answer 9

lare problems are disproportionately harder to solve than smaller problems

Question 10

algorithm

Answer 10

the set of rules that define how a particular problem can be solved in finite number of steps
-contains finite steps each of which may require one or more operations

Question 11

constraints on type of operations an alorithm van include

Answer 11

1. each operation must be DEFINITE
   - must be clearly defined what should be done
   - cant say add 3 and a, since the operation is not defined
2. each operation must be EFFECTIVE
   - each step should also be able to be done by pen and paper in finite amount of time
   - arithmetic operators on interes are effective but on real numbers, its not effective
   since vales come in infinitely lon decimal expansions
3. each operation must be FINITE
   - the alorithm should terminate after a finite number of operations

Question 12

characteristics of a good algorithm

Answer 12

1. PRECISION - steps should be precisely define
2. UNIQUENESS - every step should uniquely contribute to the algorithm
   - result of a step is unique and depends on input and the results of the previous steps before it ONLY
3. FINITENESS - must be finite and should terminate
4. INPUT - algorithm requires specific input to work on
5. OUTPUT - algorithm produces output as per input received and stated objectivities
6. OUTPUT -

Question 13

components of an algorithm

Answer 13

1. INPUT - provoided by user or elf obtained like readin from a file
2. PROCESSIN -
3. OUTPUT - the objective of the algorithm

Question 14

program and algorithm relation

Answer 14

a program is the expression of an algorithm in a prorammin lanuae

Question 15

algorithm can be expressed in what ways

Answer 15

1. FLOWCHART

2. PSEUDO - CODE

Question 16

FLOWCHART

Question 17

functions of flowcharts

Answer 17

1. pictorially depicts the sequence in which instructions are carried out in an algorithm
2. used as an aid in developing algorithms

Question 18

flowchart symbol - OVAL

Answer 18

start and stop

Question 19

flowchart symbol - PARALLELORAM

Answer 19

input and output

Question 20

flowchart symbol - RECTANLE

Answer 20

processin

Question 21

flowchart symbol - DIAMOND

Answer 21

decision box

Question 22

flowchart symbol - CIRCLE

Answer 22

connector ???

Question 23

—–>—- and upward arrow

Answer 23

flow of control symbol

Question 24

_
I
———-
I_

Answer 24

annotation

Question 25

pseudo code

Answer 25

it is an informal lanuae - helps programmers describe steps of a proram's solution without usin any prorammin lanuae syntax - it is a text based detail alorihmic dein tool - creates an outline or rouh draftof a proram that ives the idea od how the alorithm works and how conrol flows from one step to another

Question 26

notes of pseudo code

Answer 26

1. there are NO STANDARD RULES o write a pseudocode | 2. TOTALLY INFORMAL WAY of representin an alortihm

Question 27

advantages of a pseudo code

Answer 27

1. uses elish - easy to understand 2. hih;hts the seuqnce of instructions 3. structure of alorithm is clealry visible - for ex: selection and repetition blocks 4. can be easily modified sinc no dependncies

Question 28

disadvantes of pseudo cod

Answer 28

1. not a visual tool like flowchart 2. no standardization - varies from coder to coder 3. can only be tested on paper, no program to test it 4. informal representation of an algorithm

Question 29

verifyin an alorithm means?

Answer 29

to ensure that the alorithm is workin as intended | - we should test an alorithm eith sample inputs for which we know the outputs

Question 30

DRY RUN

Answer 30

process of a prorammer manually workin throuh their code to trace the value of variables. no software involved in this process

Question 31

how is dry run done

Answer 31

- print out of code - coder uses pen and paper and manually follow the value of a variable to check that it was used and updated as expected - if works incorrect, cder finds out error

Question 32

characteristics of a dry run

Answer 32

1. carried out durin desin, implementation, testin or maintennace 2. used to identify the logic error in a code 3. cannot find the execution error in a code

Question 33

trace tables

Answer 33

used in dry run of code | - each line of codeis seen on the values of variables of the alorithm

Question 34

comparin alorithms main factor

Answer 34

to decde which alorithm to choose over, EFFICIENCY is the main factor

Question 35

major factors that overn the efficiency of an alorithm are

Answer 35

1. th etime it takes to find the solution | 2. the resources which are consumed in the process

Question 36

two type of efficiences that are decidin factors for chosin alorithms

Answer 36

1. SPACE WISE EFFICIENCY - how much amt of memory the algorithm will take before it terminates - thus we consider the amt of data the alo uses when runnin 2. TIME WISE EFFICIENCY - how muchtime alo takes to complete - this factor depends on: i. RAM available ii. prorammin lanuae iii. hardware platform etc