Fundamentals of Variables

  Keywords:

Variables:

 

Every variable must have:

💬Data type

💬Name 

💬Size

💬value

Variable declaration:

Variable declaration:

Codes:

Data type sizes:

#include<iostream>

using namespace std;

int main()

{

cout<<"\nMemory Size of Data Types\n";

cout<<"Size Of short:"<<sizeof(short)<<endl; cout<<"Size Of short int:"<<sizeof(short int)<<endl;

cout<<"Size Of int:"<<sizeof(int)<<endl;

cout<<"Size Of Long int"<<sizeof(long int)<<endl;

cout<<"Size Of Long"<<sizeof(long)<<endl; cout<<"Size Of long long:"<<sizeof(long long)<<endl; cout<<"Size Of float:"<<sizeof(float)<<endl;

cout<<"Size Of double"<<sizeof(double)<<endl; cout<<"Size Of long double"<<sizeof(long double)<<endl;

}

Variable decleration:

#include<iostream>

using namespace std;

int main()

{

int age;  //variable declaration

age =30;  //assignment operation on variable age

int marks = 100; // variable definition i.e variable created as well as initialized

cout<<"age:"<<age<<" marks:"<<marks<<endl;

//overwriting previous values of variables age and marks

age = 31;

marks=98;

cout<<"Displaying new values of age and marks"<<endl;

cout<<"age:"<<age<<" marks:"<<marks<<endl;

}