Data Types And Operators in C++ Programming

Data Types in C++

Data type means which type of data will be stored in a variable. There are three primitive or basic data types in C++ programming

·        char (stores alphabets, numbers and special characters as String)

·        int (stores whole numbers)

·        float(stores decimal numbers)

See the following table for more details 

Type	Storage size	Value range	Precision
char	1 byte	-128 to 127 or 0 to 255	NA
unsigned char	1 byte	0 to 255	NA
signed char	1 byte	-128 to 127	NA
int	2 or 4 bytes	-32,768 to 32,767 or -2,147,483,648 to 2,147,483,647	NA
unsigned int	2 or 4 bytes	0 to 65,535 or 0 to 4,294,967,295	NA
short	2 bytes	-32,768 to 32,767	NA
unsigned short	2 bytes	0 to 65,535	NA
long int	4 bytes	-2,147,483,648 to 2,147,483,647	NA
unsigned long	4 bytes	0 to 4,294,967,295	NA
float	4 byte	1.2E-38 to 3.4E+38	6 decimal places
double	8 byte	2.3E-308 to 1.7E+308	15 decimal places
long double	10 byte	3.4E-4932 to 1.1E+4932	19 decimal places

 

·        Unsigned Means only +(positive)

·        Signed Means both + (positive) and – (negative)

·        Long means higher storage size

·        As int stores the numbers between -32,768 to 32,767 but long int stores between  -2,147,483,648 to 2,147,483,647

Operators in C++

Operators are those things which operate on operands. For Example

int a=5,b=15,c;

c=a+b;

here a,b and c are variables or operands whereas + and = are operators.

Let us see more explanation:

There are 3 categories of operators in C++ programming:

 

·        Arithmetic Operators

o   +  (Arithmetic Sum)

o   –  (Arithmetic Subtraction)

o   *  (Arithmetic Multiplication)

o   /   (Arithmetic Division)

o   %  (Arithmetic Modulus or Remainder)

o   =   (Arithmetic Assignment)

·        Relational Operators

o   <   (Less Than)

o   <= (Less Than or Equal To)

o   >   (Greater Than)

o   >= (Greater Than or Equal To)

o   == (Equal To)

o   !=  (Not Equal To)

·        Logical Operators

o   && (AND) (When all the joined conditions are true)

o   ||   (OR) (When any of the joined conditions are true)

o   !      (NOT) (When condition is not true)

 

Coding Examples of Operators:

·        Arithmetic Operators

Arithmetic operators like +, - , *(Multiplication) and = (Assignment) are easy to understand.  Here I would like to show the working of two Arithmetic operators / and %. See the following code :

 

int a=15,b=6,c=0;

c=a/b;  [ c will hold 2 as c is an integer variable and does not hold decimal ]

c=a%b; [c will hold 3 as % operator gives remainder of a divided by b]

 

·         Relational Operators

// Following Program uses relational operators.

Line 1.                 #include<iostream.h>

Line 2.                void main()

Line 3.                {

Line 4.                int a,b;

Line 5.                cout<< “Enter two Numbers”;

Line 6.                cin>>a>>b;

Line 7.                if(a<b)

Line 8.                {

Line 9.                cout<<” a is less than b”;

Line 10.           }

Line 11.           else if(a>b)

Line 12.           {

Line 13.           cout<<” a is greater than b”;

Line 14.           }

Line 15.           else if(a= =b)

Line 16.           {

Line 17.           cout<<” a and b are equal”;

Line 18.           }

Line 19.           }

 

Explanation: We can see that at Line 7,Line 11 and Line 15 there are conditions used using relational operators.

 

·        Logical Operators

/* Following Program displays “Number Even and less than 10”, “Number Even but not less than 10”, “Number Either Even or less than 10 or both” Message depending on the value of variable “a”.*/

Line 1.                 #include<iostream.h>

Line 2.                void main()

Line 3.                {

Line 4.                int a,b;

Line 5.                cout<< “Enter A Number”;

Line 6.                cin>>a;

Line 7.                if(a<10 && a%2==0)

Line 8.                {

Line 9.                cout<<” Number Even and less than 10”;

Line 10.           }

Line 11.           else if(!(a<10) && a%2==0)

Line 12.           {

Line 13.           cout<<” Number Even but not less than 10”;

Line 14.           }

Line 15.           else if(a<10 || a%2==0)

Line 16.           {

Line 17.           cout<<” Number Either Even or less than 10 or both”;

Line 18.           }

Line 19.           }

 

Explanation: We can see that at Line 7,Line 11 and Line 15 there are conditions used using relational operators combined with Logical Operators.

 

·        Difference between “=” and “= =” operators

=	==
Arithmetic Assignment Operator	Relational Operator
It assigns value from right to left. For Example int a = 5;	It checks the value for equality. For Example if(a==5)

 

·        Conditional Operator or Ternary Operator (? :)

If there are three variables “a”, “b” and “c’ and we want “c” to store the higher value of “a” or “b” , we can use the following code:

Line 1.           #include<iostream.h>

Line 2.           void main()

Line 3.           {

Line 4.           int a ,b, c;

Line 5.           cout<<”Enter 2 Numbers”;

Line 6.           cin>>a>>b;

Line 7.           if(a>b)

Line 8.           {

Line 9.           c=a;

Line 10.      }

Line 11.      else

Line 12.      {

Line 13.      c=b;

Line 14.      }

Line 15.      }

We required 15 lines of code. But we can do the same thing in less number of lines using ternary or conditional operator (? :)

Line 1.            #include<iostream.h>

Line 2.           void main()

Line 3.           {

Line 4.           int a ,b, c;

Line 5.           cout<<”Enter 2 Numbers”;

Line 6.           cin>>a>>b;

Line 7.           c=(a>b)? a : b;

Line 8.           }

 

We saw that we have reduced nearly half of the lines. At Line 7, we have used conditional operator which evaluates a condition. If condition is true, variable before the colon (:) is assigned to c otherwise if condition is false, variable after the colon(:) is assigned to c.