DEV Community: Ram Kumar Shukla

class and objects in c++

Ram Kumar Shukla — Mon, 14 Dec 2020 00:49:07 +0000

hey there, today we will talk about class and instances in c++.

Class

c++ supports object-oriented programming and often called user defined data types.
A class is a blueprint of the object. Data and functions within a class are called member of the class.

definition of class

class Circle{
      public:
        double radius; //radius of the circle
};

class definition is starts with keyword class followed by classname. Here public means members of the class are accessible from outside the class from anywhere within scope of the class.

Class Objects

Circle circle1; //Declare circle1 of type Circle
Circle circle2; //Declare circle2 of type Circle

class objects/instances are defined by exactly the same way we define basic variables. class name followed by object name.

#include <iostream>
#include <cmath>

using namespace std;

class Circle{
     public:
       double radius;
};

int main(){
  //Objects instantiations
Circle circle1;
Circle circle2;
double area = 0.0; //Store the area of the circle here

circle1.radius = 2.1;
circle2.radius = 5.3;

// Area of the circle1
area = 3.14 * pow(circle1.radius, 2);
cout << "Area of the circle is " << area << endl;

// Area of the circle2
area = 3.14 * pow(circle2.radius, 2);
cout << "Area of the circle is " << area << endl;

return 0;
}

when above code compiled and executed, it will produce a follwing result.

Area of the circle is 13.8474
Area of the circle is 88.2026

what is buffer in c/c++?

Ram Kumar Shukla — Sat, 12 Dec 2020 23:59:49 +0000

Buffer is a term that refers to a block of computer memory that serves as temporary storage area is called buffer. All standard input and output device contains an input and output buffer.
Some of the example of the buffer...

Computer which uses RAM as buffer.
In a video streaming a sections of the movie you are streaming downloads to your device to stay ahead of your viewing.

Data can placed in software buffer before it is processed, writing data to a buffer is much faster than direct operation.
using a buffer while programing in C/c++ speeds up calculation process. Buffers come in handy when a difference exists between the rate data is received and the rate it is processed.

If you want to store a array of characters after a some input to store that in desired location, then you must need to clear unwanted buffer first so as to get the next input in desired location.

cin.ignore() is used to ignore or clear one or more characters from the input buffer.

What is Digital Ocean and it's history?

Ram Kumar Shukla — Fri, 11 Dec 2020 15:30:12 +0000

what is digital ocean?

Digital Ocean is an cloud hosting provider that offer cloud computing services. In January 2018, it achieved the title of being third largest cloud hosting company in the world. They are highly obsessed to provide a best cloud hosting Plateform from individual developer to large scale business. Digital Ocean is a cloud server providers based on United states of America. Their headquarter operates from New York city and they have lots of Data center across the globe.

History

It came into existence on June 24th 2011. Ben and Moisey Uretsky founders of the Digital Ocean. They founded this company that provides individual software develpoer and small scale startups making it easy for them to host website with one click.