Functions allow code to be reused by grouping a series of statements together to perform a specific task. A function definition specifies the data types of parameters and return values, and the function body contains the statements. Functions are called by their name followed by parentheses, and actual arguments are passed inside the parentheses. Parameters act as variables that represent the arguments passed into the function.

1. Introduction to
Software
Engineering

2. CONTENTS OF THIS COURSE
Here’s what you’ll find in this LECTURE1:
 Functions
 Data type.
 Numeral System.
 Variables.
 Visualize code using Visualizer.

3. Lecture 1

4. “Let’s make the world a
better place”

5. Functions
• You can think of function as a black box take an input and
produce an output and it’s not important to know what is
the algorithm inside of it , just enough to know how you can
use and what is their function.
Hello,World

6. Functions

7. Data types
• Fixed values such as numbers, letters, and strings are called
“constants”
• String constants use single quotes (') or double quotes (")

8. Data types
• Numerical Data int, float, double.
• Textual Data string, char.
• Bolean Data true, false.

9. Some common Compiler errors
• Forgetting the semicolon ;
• Forgetting to one the curly braces of the main function { }
• Forgetting the “ “ in a string.

10. Some common Compiler errors
 performs calculations
a billion calculations per second! two operations in same
time light travels 1 foot.
 Remembers results
100s of gigabytes of storage!
typical machine could hold 1.5M books of standard size

11. Variables

12. Variables
• You can think of variable as a little box or a container to
store data in the memory of the computer and later
retrieve the data using the variable “name”
• Programmers get to choose the names of the variables
• You can change the contents of a variable in a later
statement

13. Variables

14. Rules for naming variables in C++
 The first character of the name must be a letter or an underscore.
 Only letters, digits, or underscores can follow the first letter. Blank
spaces aren’t allowed; separate words in a multiple-word identifier
are indicated by capitalizing the first letter of one or more of the
words. (Although underscores can also be used for this purpose,
they are increasingly being used only for compiler-dependent
identifiers.)
 An identifier name can’t be one of the keywords listed in Table 1.1.
(A keyword is a word the language sets aside for a special purpose
and can be used only in a specified manner. 4 )
 The maximum number of characters in an identifier is 1024.

15. Rules for naming variables in C++

16. Wrong Naming examples
 3number ●
 total salary ●
 private

17. Variables

18. Variables

19. Variables

20. Variables

21. Variables

22. Arian 5 the worst bug disaster
On June 4th, 1996, the very first Ariane 5 rocket ignited its
engines and began speeding away from the coast of French
Guiana. 37 seconds later, the rocket flipped 90 degrees in
the wrong direction, and less than two seconds later,
aerodynamic forces ripped the boosters apart from the
main stage at a height of 4km.

23. Arian 5 the worst bug disaster
On June 4th, 1996, the very first Ariane 5 rocket ignited its
engines and began speeding away from the coast of French
Guiana. 37 seconds later, the rocket flipped 90 degrees in
the wrong direction, and less than two seconds later,
aerodynamic forces ripped the boosters apart from the
main stage at a height of 4km.

24. More Variables

25. Comments in C++
Comments in C++ begin with // character and continue to the end of the line.
Because comments do not execute, when you run a program you will not see
any indication of the comment there. Comments are in the source code for
humans to read, not for computers to execute.

26. More Variables

27. Constant Value
● Constant values can not be overwritten.
● You must assign a value to it.

28. Numeric Expressions
Operation
Operator
Addition
+
Subtraction
-
Multiplication
*
Division
/
Remainder
%

29. Escape Sequence

30. User Input
C++ has an input function which lets you ask
a user for some text input

31. Input / Output in C++
cout (Console Output)
cin (Console Input)

32. Conditions
C++ uses boolean logic to evaluate conditions. The boolean
values True and False are returned when an expression is
compared or evaluated.

33. Conditions

34. Conditions
C++ uses boolean logic to evaluate conditions. The boolean
values True and False are returned when an expression is
compared or evaluated.

35. Conditions
C++ uses boolean logic to evaluate conditions. The boolean
values True and False are returned when an expression is
compared or evaluated.

36. Conditions-Logic Gates
A Logic gate is a kind of the basic building block of a digital
circuit having two inputs and one output. ... Logic gates are
used to carry out the logical operations on single or
multiple binary inputs and result in one binary output. In
simple words, logic gates are the electronic circuits in a
digital system.

37. Conditions-Logic Gates

38. Bitwise Operator

39. Precision in floating point in CPP
 floor(), ceil(), round(), setprecision()

40. Loop
Python has two primitive loop commands:
1.while loops
2.for loops

41. Loop
 C++ has two primitive loop commands:
while loops

42. Loop
 C++ has two primitive loop commands:
for loops

43. Break and continue

44. Do- while

45. Function
How can we create a glass box.