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Example:

long int days;

unsigned int num_of_days;

The reserved words unsigned int are used to specify an integer that can only store nonnegative numbers.

The signed and unsigned quantifiers tell the compiler how to use the sign bit with integral types and characters (floating-point numbers always contain a sign). An unsigned number does not keep track of the sign and thus has an extra bit available, so it can store positive numbers twice as large as the positive numbers that can be stored in a signed number.

Integer types with quantifiers

When you are modifying an int with short or long, the keyword int is optional.

Now all the built-in data types provide by C++ are given in the following list, ordered descendingly by the size of the data types.

Data types

--------------

long double

double

float

unsigned long

long int

unsigned int

int

short in

char

Data type conversions

An expression containing both integer and floating point operands is called a mixed mode expression.

Example:

int a;

float x = 2.5;

a = x + 6; // x + 6 is a mixed mode expression

Note: We should avoid mixed-mode expression.

Examples:

char Ch;

int In1 = 129, In2, In3;

double Real1 = 12.34, Real2;

What happens with the following mixed mode assignments?

Ch = In1/2 + 1; // Right side = 65; assigns ‘A’ to Ch

In2 = Ch + 1; // Right side = 66; assigns 66 to In2

Real2 = In1/2; // Right side = 64; assigns 64.0 to Real2

In3 = Real1/2.0 // Right side = 6.17; truncates this value and assigns 6 to In3

The general rules for converting integer and floating point operands in mixed mode arithmetic expressions were presented as follows:

  1. If both operands are either character or integer operands:
    • when both operands are character, short or integer data types, the result of the expression is an integer value.
    • when one of the operand is a long integer, the result is a long integer, unless one of the operand is an unsigned integer. In the later case, the other operand is converted to an unsigned integer value and the resulting value of the expression is an unsigned value.
  2. If any one operand is a floating point value:
    • when one or both operands are floats, the result of the operation is a float value;
    • when one or both operands are doubles, the result of the operation is a double value;
    • when one or both operands are long doubles, the result of the operation is a long double value;

Notice that converting values to lower types can result in incorrect values. For example, the floating point value 4.5 gives the value 4 when it is converted to an integer value. The following table lists the built-in data types in order from “highest type” to “lowest type”.

Determining storage size

C++ provides an operator for determining the amount of storage your compiler allocates for each data type. This operator, called the sizeof() operator.

Example:

sizeof(num1)

sizeof(int)

sizeof(float)

The item in parentheses can be a variable or a data type.

Example

// Demonstrating the sizeof operator

#include<iostream.h>

int main()

{

char c;

short s;

int i;

long l;

float f;

double d;

long double ld;

cout<<"sizeof c = "<<sizeof(c)

Questions & Answers

what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Programming fundamentals in c++. OpenStax CNX. Jul 29, 2009 Download for free at http://cnx.org/content/col10788/1.1
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