This document discusses the key phases of the Software Development Method (SDM) framework: specification of needs, problem analysis, design and algorithmic representation, implementation, testing and verification, and documentation. It provides details on each phase, including defining the problem and needed solution, identifying inputs/outputs, designing algorithms using pseudocode and flowcharts, implementing the program, testing it, and documenting the process. Pseudocode and flowcharts are presented as ways to formally represent algorithms using basic structures like sequence, selection, and repetition. The document emphasizes that documentation should be an ongoing process throughout the entire software development lifecycle.

1. My first slides
Designed by:
Iqra Aleem

2. PROGRAMMING FUNDAMENTALS
Course Code: 104
BSCS: 1st Semester

3. Software Development Method
What is SDM?
A framework that describes the activities
performed at each stage of a software
development project.

4. Phases
Specification of needs
Problem analysis
Implementation
Testing and
Verification
Design and
Algorithmic
Representation
Documentation

5. Specification of Needs
In this phase we actually learn about:
 What the problem is
 What is needed to solve it
 What solution should provide
 If there are constraint and special conditions.

6. Problem analysis
In this phase we should identify
following:
 Input to the problem, their form and input media
to be used
 Output expected, their form and output media to
be used
 Special constraints and conditions
 Formulas or equations to be used.

7. Design andAlgorithmic Representation
 An algorithm is a sequence of infinite number of
steps arranged in a specific logic order which,
when executed, produces the solution for a
problem
An algorithm must satisfy these
requirements:
 It may have an input
 It may have an output
 It should not be ambiguous
o Every step in algorithm must be clear as what is supposed to
do

8. Design andAlgorithmic Representation cont….
 It must be general
 It must be correct and it must solve the problem for which
it is designed
 It must execute and terminate in a finite amount of time
 It must be efficient enough so that it can solve the
intended problem using the recourses currently available
on the computer
 An algorithm can be represented by using:
orPseudo codes Flow chart

9. Control Structure
 In order to tackle a problem, we need:
 A correct algorithm
 To apply the algorithm at the good moment
 To decide which algorithm to apply
 To know if a certain operation to be repeated
 An algorithm can be described using only three
control structures:
sequence selection reputation

10. Pseudocodes
 A pseudocode is a semiformal, english-like
language with limited vocabulary that can be
used to design and describe algorithm
 Criteria of a good pseudocode:
 Easy to understand, precise and clear
 Gives correct solution in all cases
 Eventually end

11. Pseudocodes: the sequence control structure
 A series of steps or statement that are executed in the order they
are written in algorithm
 The beginning and ends of a block of statement can be optionally
marked with keywords begin and end.
o Example:
Begin
Read the birth date from user.
Calculate the difference between birth date and today’s date.
Print the user age.
End

12. Pseudocodes: The selection control structure
 Defines two courses of action depending on outcome
of a condition. A condition is an expression that is,
when computed, evaluated either true or false.
 The keywords used are if and else.
if condition if age is greater than 23
then-part printf “retire”
Else else
Else-part print “work work
work”
end_if end_if
Format Example

13. Pseudocodes: The repetition control structure
 The repetition control structure may be like this
example:
 Summing up to 10 numbers
Cumulative sum =0
current num = 1
while current num is less or equal to 10
cumulative sum = cumulative sum + current number
current number = current number + 1
end_while
print the value of cumulative number
o In this algorithm, we have used both sequence and repetition control
structure.

14. Flow charts
 Flow chart is a graph used to depict or show a step by step
solution using symbols which represent a task.
 The symbols used consists of geometrically shapes that
are connected by flow lines.
 Flow chart is graphical in nature.

15. Flowchart symbols
Terminal symbol-indicates the beginning and ending
points.
Process symbol-shows an instruction.
Input/output symbol- shows an input/output
operations
Disk storage-indicates input or output from disk storage.
printer output symbol- shows hard copy printer output
selection symbol-shows a selection process for two way
selection.
off page connector-provides continuation of a logical
path of another page.

16. Flow chart symbols cont….
On page connector-provides continuation of a logical path at another
point of the same page.
flow lines-indicates the logical sequence of execution steps.
 Flow chart –sequence control structure:
statement1
statement2
:

17. Flow chart-selection control structure
It’s may be in this form
condition
Else- statement Then-statement

18. Flow chart- repatriation control structure
 It’s may be like this
yes
no
condition
Loop
statement

19. Implementation
 The process of implementing on algorithm by writing a
computer program using a programming language.
 The output of the program must be solution of problem.
 The program must not do anything that is not supposed to
do
 (think of those may viruses, buffer overflow, trogon horses
etc, that we experience almost daily . All these results
from programs doing more than they were intended to do)

20. Testing and verification
 Program testing is the process of executing a program
to demonstrate its correctness
 Program verification is the process of ensuring that a
program meets user requirements
 After the program is compiled , we must run the
program and verify it with different inputs before the
program can be released to the public or other users

21. Documentation
 Contains details produced at all stages of program
development cycle.
 It can be done in two ways:
 Writing comments between your lines of codes
 Creating a separate text file to explain the program
 Important not for only other people to use or modify your
program, but also for you to understand your own program
after a long time

22. Documentation conti…..
 Documentation is important because:
 You may return to this program in future to use the whole of or part of
it again
 Other programmer or end user will need some information about your
program for reference or maintenance
 You may some day have to modify the program or may discover
errors in your program
 Although documentation is listed as the last stage of
software development method , it is actually an ongoing
process which should be done from very beginning of
software development method.

23. .
Thank you