1. DATA HANDLING

2. DATA HANDLING
C++ Data Types
Derived types
Fundamental types

3. FUNDAMENTAL TYPES Those data types that are not composed
of other data types
int Data types ( for integers)
char Data type ( for characters)
float Data type (for floating–point numbers)
double Data type (for double precision floating–
point numbers)
void Data type (for empty set of values and non-
returning functions)

4. int Datatype
They have no fractional part. An identifier declared as int becomes an integer variables and can hold integer values only

5. char Datatype
Characters can store any member of the C++ implementation’s basic character set. If a character from this set is stored in a character variable, its value is equivalent to the integer code of that character. An identifier declared as char becomes a character variable.

6. float Datatype
A number having fractional part is known as floating point number. An identifier declared as float becomes a floating-point variable and can hold floating-point numbers only
E.g (or E02) , 12.0 etc.,

7. double Datatype Occupies twice as much memory as type float.
Stands for double precision floating-point.
Used when type float is too small or insufficiently precise.

8. void Datatype Specifies an empty set of values
Used as the return type for functions that do not return a value.
No object of type void is declared

9. DATA TYPE MODIFIERS
signed
unsigned
long
short

10. Integer Types short unsigned Signed short 2 - 32768 to 32767
Approximate Size
(in bytes)
Minimal Range
short
unsigned
Signed short 2
to 32767
0 to 65,535
same as short
int
unsigned int
signed int 2
to 32767
0 to 65,535
same as int
long
unsigned long
signed long 4
- 2,147,483,648 to 2,147,483,648
0 to 4,294,967,295
same as long

11. Character Types Char unsigned char signed short 1 - 128 to 127
Approximate Size
(in bytes)
Minimal Range
Char
unsigned char
signed short 1
- 128 to 127
0 to 255
same as char

12. Floating-point Types 1.7 × 10-38 to 1.7 × 10-38 -1
Approximate Size
(in bytes)
Minimal Range
Digits of precision
float
double
long double 4 8 10
- 3.4 × to ×
1.7 × to 1.7 ×
3.4 × to 3.4 × 7 15 19

13. DERIVED DATA TYPE
Arrays
Function
Pointer
Reference
Constant

14. ARRAYS Named list of finite number n of similar data element
Each of the data elements can be referenced respectively by a set of consecutive numbers, usually 0,1,2,3, …. n.

15. FUNCTION
Its named part of a program that can be invoked from other parts of the program as often needed.

16. POINTER
It’s a memory variable that can hold a memory address. This address is usually the location of another variable in memory
Memory Addresses
Value
In Memory
Variable
Names A B
Syntax
type * ptr ;
E.g. int * A, B; A= &B;
1053

17. REFERENCE An alternative name for an object.
Declaration consists of a base type, an & (ampersand), a reference variable name equated to a previously defined variable name.
type & ref-var = var-name;
E.g.
int total = 100;
int & sum = total;
count<<sum<<total<<“\n”;
Output 100
100

18. CONSTANT Value cannot be altered during the program run.
Must be initialized at the time of declaration.
Const type name = value

19. USER-DEFINED DERIVED DATA TYPES
class
structure
union
enumeration

20. objects of class department
A class bears the same relationship to an object as a type bears to a variable
Eg. class department { char name[20]
int empno;
char hod[20];
public:
void add( );
void get( );
void print( ); };
department sales, accounts;
objects of class department

21. STRUCTURE
It’s a collection of variables of different data types referenced under one name
Eg. struct studrec { int rollno;
char name[20];
int class;
float marks;
char grade; };
studrec newstu;
The elements are referenced as newstu.rollno, newstu.name etc.,
objects of structure
studrec

22. UNION
A memory location that is shard by two ore more different variables of different types at different time.
E.g., union share { int i ;
char ch; };
union share cvt;
cvt. i = 20;
cout<<cvt.ch
Output = 20;
Union is used for both
Declaration and definition

23. ENUMERATION An alternative method for naming integer constant.
Enum {START , PAUSE, GOO};
i.e., const int START = 0;
const int PAUSE = 1;
const int GOO = 2;

24. VARIABLES
Named storage locations whose value can be manipulated during program run.
Memory Addresses
Data Value
of varaible
Variable’s
Names A B
Syntax
type name ;
E.g. int A, B; A= 10, B = 25;
const int amount = 20;
10 25

25. FORMATTING OUTPUT setw ( ) setprecision( )
To use these i/o manipulators
include the header file
iomanip.h

26. setw( ) manipulator
Sets the width of the field assigned for the output
Takes the size of the field as a parameter
Eg.,cout<<setw(8)<<2<<“\n”;
cout<<setw(8)<<4444<<“\n”;
cout<<setw(8)<<666666<<“\n”;
OUT PUT

27. setprecision( ) manipulator
Sets the total number of digits to be displayed when floating point numbers are printed.
Sets the number of decimal places to be displayed.
Eg.,
1. cout<<setprecision(5)<< ;
OUT PUT = (rounding the digits)
2. cout.setf(ios :: fixed) ;
cout<<setprecision(5)<< ;
OUT PUT = (no rounding)

28. ADDITIONAL IOS FLAGS left right showpoint uppercase etc.,
Eg.; cout.setf(ios :: fixed);
cout.setf(ios :: showpoint);
cout<<setprecision(2);
cout<<5.8
OUTPUT
5.80