Top C++ programs for geeks for interview that will help you to understand the basic logic and by using this you can write more programs.
We’ve put up a collection of simple and complex C++ program for beginners and professionals to learn with.
Table of Contents
Print Hello World in C++
#include <iostream>
using namespace std;
int main()
{
cout << "Hello World!";
return 0;
}
Output: Hello World!
Enter two numbers and find addition in C++.
#include <iostream>
using namespace std;
int main()
{
int a;
int b;
cout<<"Enter two numbers: ";
cin>>a;
cin>>b;
cout<<"Sum of two numbers is "<<a+b;
return 0;
}
Output: Enter two numbers: 10 20 Sum of two numbers is 30
Input any character and print on screen.
#include <iostream>
using namespace std;
int main()
{
char c;
cout<<"Enter any character: ";
cin.get(c);
cout<<"Entered character is: ";
cout.put(c);
return 0;
}
Output: Enter any character: G Entered character is: G
Enter any string and print on screen.
#include <iostream>
using namespace std;
int main()
{
char c[15];
cout<<"Enter any String: ";
cin.getline(c, 15);
cout<<"Entered string is: "<< c << endl;
cout.write(c, 15);
return 0;
}
Output: Enter any String: GeekCer! Entered string is: GeekCer! GeekCer!
Enter any string and display using read and write method.
#include <iostream>
using namespace std;
int main()
{
char name[20];
cout<<"Enter any String: ";
cin.read(name, 20);
cout<<"Entered string is: "<< name << endl;
cout.write(name, 20);
return 0;
}
Output: Enter any String: Welcome To GeekCer! Entered string is: Welcome To GeekCer! Welcome To GeekCer!
Program to display decimal, octal and hexadecimal value.
#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
int value = 10;
cout<<"Decimal base: "<<setbase(10)<<value;
cout<<"\nHexadecimal base: "<<setbase(16)<<value;
cout<<"\nOctal base: "<<setbase(8)<<value;
return 0;
}
Output: Decimal base: 10 Hexadecimal base: a Octal base: 12
Program to perform operation using variable.
#include <iostream>
using namespace std;
int main()
{
int a, b;
int result;
a = 15;
b = 5;
a = a + 1;
result = a - b;
cout << "Result: " << result;
return 0;
}
Output: Result: 11
Initialize the variables in constructor initialization way.
#include <iostream>
using namespace std;
int main()
{
int a = 10; // initial value = 10
int b(2); // constructor initialization = 2
int result;
a = a + 3;
result = a - b;
cout <<"Result: " << result;
return 0;
}
Output: (You can use Dev C++ compiler) Result: 11
Program of string assignment in C++.
#include <iostream>
#include <string>
using namespace std;
int main()
{
string testString;
testString = "This is the first string content";
cout << testString << endl;
testString = "This is a second string content";
cout << testString << endl;
return 0;
}
Output: This is the first string content This is a second string content
Find the greater number using conditional operator.
#include <iostream>
#include <string>
using namespace std;
int main()
{
int a, b, c;
a = 10;
b = 20;
c = (a > b) ? a : b;
cout<<"Greater number is "<< c;
return 0;
}
Output: Greater number is 20
Program to enter any number and display.
#include <iostream>
using namespace std;
int main()
{
int n;
cout << "Please enter any number: ";
cin >> n;
cout << "The number you entered is " << n;
return 0;
}
Output: Please enter any number: 100 The number you entered is 100
Know more about Top HR Interview Questions and Answers for Job Seekers
Write a program to input string and display using cin.
#include <iostream>
#include <string>
using namespace std;
int main()
{
string str;
cout << "What is your name? ";
getline (cin, str);
cout << "Hello " << str << ".\n";
cout << "What is your favorite sport? ";
getline (cin, str);
cout << "I like " << str << " too!\n";
return 0;
}
Output: What is your name? Cyber Geek Hello Cyber Geek. What is your favorite sport? Cricket I like Cricket too!
Input information and display using stringstream.
#include <iostream>
#include <sstream>
#include <string>
using namespace std;
int main()
{
string str;
float price = 0;
int quantity = 0;
cout << "Enter price: ";
getline (cin, str);
stringstream(str) >> price;
cout << "Enter quantity: ";
getline (cin, str);
stringstream(str) >> quantity;
cout << "Total price: " << price*quantity << endl;
return 0;
}
Output: Enter price: 5000 Enter quantity: 20 Total price: 100000
Program to implement countdown using while loop.
#include <iostream>
using namespace std;
int main()
{
int n;
cout << "Enter the starting number : ";
cin >> n;
while (n > 0)
{
cout << n << ", ";
--n;
}
cout << "Finish!\n";
return 0;
}
Output: Enter the starting number : 10 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, Finish!
Program for compound assignment operators.
#include <iostream>
using namespace std;
int main()
{
int a, b=5;
a = b;
a += 2; // Equivalent to a=a+2
cout << "Result: " << a;
return 0;
}
Output: Result: 7
Write a program to break loop using break statement.
#include <iostream>
using namespace std;
int main()
{
int i;
for (i = 10; i > 0; i--)
{
cout << i << ", ";
if (i == 5)
{
cout << "Countdown Aborted!";
break;
}
}
return 0;
}
Output: 10, 9, 8, 7, 6, 5, Countdown Aborted!
Write a program by using continue statement.
#include <iostream>
using namespace std;
int main()
{
int i;
for (i = 10; i > 0; i--)
{
if (i == 3) // Skipped 3
{
continue;
}
cout << i << ", ";
}
cout << "Finish!";
return 0;
}
Output: 10, 9, 8, 7, 6, 5, 4, 2, 1, Finish!
C++ program using goto statement.
#include <iostream>
using namespace std;
int main()
{
int i = 10;
loop:
cout << i << ", ";
i--;
if (i > 0) goto loop;
cout << "Finish!";
return 0;
}
Output: 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, Finish!
Program using function to add two numbers.
#include <iostream>
using namespace std;
int addition (int a, int b)
{
int sum;
sum = a + b;
return sum;
}
int main()
{
int sum;
sum = addition (10, 30);
cout <<"Addition is "<< sum;
return 0;
}
Output: Addition is 40
Write a program of void function.
#include <iostream>
using namespace std;
void displayMessage ()
{
cout << "This is a function!";
}
int main()
{
displayMessage ();
return 0;
}
Output: This is a function!
Program for passing parameter by reference.
#include <iostream>
using namespace std;
void call (int& a, int& b, int& c)
{
a *= 3;
b *= 2;
c *= 4;
}
int main()
{
int x=1, y=3, z=7;
call (x, y, z);
cout << "x=" << x << ", y=" << y << ", z=" << z;
return 0;
}
Output: x=3, y=6, z=28
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C++ program to return more than one values from function.
#include <iostream>
using namespace std;
void getvalue (int x, int& prev, int& next)
{
prev = x-1;
next = x+1;
}
int main()
{
int x = 10, y, z;
getvalue (x, y, z);
cout << "Previous=" << y << ", Next=" << z;
return 0;
}
Output: Previous=9, Next=11
C++ program to pass default value in the function.
#include <iostream>
using namespace std;
int multiplication (int a, int b=2)
{
int result;
result =a * b;
return result;
}
int main()
{
cout << multiplication (10);
cout << endl;
cout << multiplication (20, 4);
return 0;
}
Output: 20 80
Write a program of function overloading.
#include <iostream>
using namespace std;
int calculate (int a, int b)
{
return (a + b);
}
float calculate (float a, float b)
{
return (a / b);
}
int main()
{
int x=10, y=20;
float n=25.0, m=5.0;
cout <<"Addition: "<< calculate (x, y);
cout << "\n";
cout <<"Division: "<< calculate (n, m);
return 0;
}
Output: Addition: 30 Division: 5
Write a program of functions prototypes.
#include <iostream>
using namespace std;
void odd (int a);
void even (int a);
int main()
{
int n;
do {
cout << "Type a number (0 to exit): ";
cin >> n;
if (n != 0)
{
odd (n);
}
} while (n!=0);
return 0;
}
void odd (int a)
{
if (a % 2 != 0)
cout << "Number is odd.\n";
else
even (a);
}
void even (int a)
{
if (a % 2==0)
cout << "Number is even.\n";
else
odd (a);
}
Output: Type a number (0 to exit): 2 Number is even. Type a number (0 to exit): 6 Number is even. Type a number (0 to exit): 7 Number is odd. Type a number (0 to exit): 5 Number is odd. Type a number (0 to exit): 11 Number is odd. Type a number (0 to exit): 0
Program to initialize and access the array.
#include <iostream>
using namespace std;
int main()
{
int arr [] = {10, 20, 30, 40, 50};
int n, sum=0;
for ( n=0 ; n<5 ; n++ )
{
sum += arr[n];
}
cout <<"Sum: " << sum;
return 0;
}
Output: Sum: 150
C++ Program to pass arrays as parameters.
#include <iostream>
using namespace std;
void display (int arg[], int length)
{
for (int i=0; i < length; i++)
cout << arg[i] << " ";
cout << "\n";
}
int main()
{
int arr1[] = {15, 10, 15};
int arr2[] = {20, 4, 60, 8, 10};
display (arr1, 3);
display (arr2, 5);
return 0;
}
Output: 15 10 15 20 4 60 8 10
Write a program of pointer and array.
#include <iostream>
using namespace std;
int main()
{
int numbers[5];
int * p;
p = numbers; *p = 5;
p++; *p = 20;
p = &numbers[2]; *p = 30;
p = numbers + 3; *p = 40;
p = numbers; *(p+4) = 50;
for (int i=0; i < 5; i++)
{
cout << numbers[i] << ", ";
}
return 0;
}
Output: 5, 20, 30, 40, 50,
Write a C++ program of pointer to function.
#include <iostream>
using namespace std;
int addition (int a, int b)
{
return (a + b);
}
int subtraction (int a, int b)
{
return (a - b);
}
int operation (int x, int y, int(*functocall)(int,int))
{
int g;
g = (*functocall)(x,y);
return g;
}
int main()
{
int m, n;
int (*minus)(int,int) = subtraction;
m = operation (7, 5, addition);
n = operation (20, m, minus);
cout <<"Result: " << n;
return 0;
}
Output: Result: 8
Top 100 C++ programs for geeks
C++ program of pointer to structures.
#include <iostream>
#include <sstream>
#include <string>
using namespace std;
struct movies
{
string title;
int year;
};
int main()
{
string str;
movies amovie;
movies * pmovie;
pmovie = &amovie;
cout << "Enter title: ";
getline (cin, pmovie->title);
cout << "Enter year: ";
getline (cin, str);
(stringstream) str >> pmovie->year;
cout << "\nYou have entered:\n";
cout << pmovie->title;
cout << " (" << pmovie->year << ")\n";
return 0;
}
Output: Enter title: Baahubali Enter year: 2015 You have entered: Baahubali (2015)
Write a program to calculate area of rectangle using class.
#include <iostream>
using namespace std;
class Rectangle
{
int x, y;
public:
void setValues (int,int);
int area ()
{
return (x*y);
}
};
void Rectangle::setValues (int a, int b)
{
x = a;
y = b;
}
int main()
{
Rectangle rect;
rect.setValues (10, 20);
cout << "Area: " << rect.area();
return 0;
}
Output: Area: 200
C++ program of class and use multiple object.
#include <iostream>
using namespace std;
class Rectangle
{
int x, y;
public:
void setValues (int,int);
int area ()
{
return (x*y);
}
};
void Rectangle::setValues (int a, int b)
{
x = a;
y = b;
}
int main()
{
Rectangle rect;
Rectangle rectb;
rect.setValues (10, 20);
rectb.setValues (5, 6);
cout << "Area using first object: " << rect.area();
cout << endl;
cout << "Area using second object: " << rectb.area();
return 0;
}
Output: Area using first object: 200 Area using second object: 30
Program using constructors and destructors in C++.
#include <iostream>
using namespace std;
class Rectangle
{
int *width, *height;
public:
Rectangle (int,int);
~Rectangle ();
int area ()
{
return (*width * *height);
}
};
Rectangle::Rectangle (int a, int b)
{
width = new int;
height = new int;
*width = a;
*height = b;
}
Rectangle::~Rectangle ()
{
delete width;
delete height;
}
int main()
{
Rectangle rect (30, 40), rectb (15, 20);
cout << "First rectangle area: " << rect.area() << endl;
cout << "Second rectangle area: " << rectb.area();
return 0;
}
Output: First rectangle area: 1200 Second rectangle area: 300
C++ program to initialize fields using constructor.
#include <iostream>
using namespace std;
class Rectangle
{
int width, height;
public:
Rectangle (int,int);
int area ()
{
return (width*height);
}
};
Rectangle::Rectangle (int a, int b) {
width = a;
height = b;
}
int main()
{
Rectangle rect (20, 10);
cout << "Area of rectangle: " << rect.area();
return 0;
}
Output: Area of rectangle: 200
Write a C++ program of constructor overloading.
#include <iostream>
using namespace std;
class Rectangle
{
int width, height;
public:
Rectangle ();
Rectangle (int, int);
int area ()
{
return width * height;
}
};
Rectangle::Rectangle ()
{
width = 10;
height = 20;
}
Rectangle::Rectangle (int a, int b)
{
width = a;
height = b;
}
int main()
{
Rectangle rect, rectb (15, 20);
cout << "First rectangle area: " << rect.area() << endl;
cout << "Second rectangle area: " << rectb.area();
return 0;
}
Output: First rectangle area: 200 Second rectangle area: 300
Write a C++ program of operator overloading.
#include <iostream>
using namespace std;
class GeekCer
{
public:
int x,y;
GeekCer () {};
GeekCer (int,int);
GeekCer operator + (GeekCer);
};
GeekCer::GeekCer (int a, int b)
{
x = a;
y = b;
}
GeekCer GeekCer::operator+ (GeekCer param)
{
GeekCer temp;
temp.x = x + param.x;
temp.y = y + param.y;
return temp;
}
int main()
{
GeekCer a (10, 20);
GeekCer b (5, 4);
GeekCer c;
c = a + b;
cout << c.x << ", " << c.y;
return 0;
}
Output: 15, 24
Program by using static members in class.
#include <iostream>
using namespace std;
class Geek
{
public:
static int n;
Geek ()
{
n++;
};
~Geek ()
{
n--;
};
};
int Geek::n=0;
int main()
{
Geek a;
Geek b[10];
Geek * c = new Geek;
cout << a.n << endl;
delete c;
cout << Geek::n << endl;
return 0;
}
Output: 12 11
Write of program of friend function in C++.
#include <iostream>
using namespace std;
class Rectangle
{
int width, height;
public:
void set_values (int, int);
int area ()
{
return (width * height);
}
friend Rectangle duplicate (Rectangle);
};
void Rectangle::set_values (int a, int b)
{
width = a;
height = b;
}
Rectangle duplicate (Rectangle rectparam)
{
Rectangle rectres;
rectres.width = rectparam.width * 2;
rectres.height = rectparam.height * 2;
return (rectres);
}
int main()
{
Rectangle rect, rectb;
rect.set_values (10, 20);
rectb = duplicate (rect);
cout <<"Area is "<< rectb.area();
return 0;
}
Output: Area is 800
Write of program of friend class in C++.
#include <iostream>
using namespace std;
class Square;
class Rectangle
{
int width, height;
public:
int area ()
{
return (width * height);
}
void convert (Square a);
};
class Square
{
private:
int side;
public:
void set_side (int a)
{
side = a;
}
friend class Rectangle;
};
void Rectangle::convert (Square a)
{
width = a.side;
height = a.side;
}
int main()
{
Square sqr;
Rectangle rect;
sqr.set_side(10);
rect.convert(sqr);
cout <<"Area is " << rect.area();
return 0;
}
Output: Area is 100
C++ program of single level inheritance.
#include <iostream>
using namespace std;
class Polygon
{
protected:
int width, height;
public:
void setValues (int a, int b)
{
width = a;
height = b;
}
};
class Rectangle: public Polygon
{
public:
int area ()
{
return (width * height);
}
};
class Triangle: public Polygon
{
public:
int area ()
{
return (width * height / 2);
}
};
int main()
{
Rectangle rect;
Triangle trgl;
rect.setValues (10, 20);
trgl.setValues (5, 10);
cout <<"Area of rectangle is "<< rect.area() << endl;
cout <<"Area of triangle is "<< trgl.area() << endl;
return 0;
}
Output: Area of rectangle is 200 Area of triangle is 25
Program of multiple inheritance in C++.
#include <iostream>
using namespace std;
class Polygon
{
protected:
int width, height;
public:
void setValues (int a, int b)
{
width = a;
height = b;
}
};
class Output
{
public:
void output (int i);
};
void Output::output (int i)
{
cout << i << endl;
}
class Rectangle: public Polygon, public Output
{
public:
int area ()
{
return (width * height);
}
};
class Triangle: public Polygon, public Output
{
public:
int area ()
{
return (width * height / 2);
}
};
int main()
{
Rectangle rect;
Triangle trgl;
rect.setValues (10, 20);
trgl.setValues (10, 10);
rect.output (rect.area());
trgl.output (trgl.area());
return 0;
}
Output: 200 50
Write a program of pointers to base class in C++.
#include <iostream>
using namespace std;
class Polygon
{
protected:
int width, height;
public:
void setValues (int a, int b)
{
width=a;
height=b;
}
};
class Rectangle: public Polygon
{
public:
int area ()
{
return width * height;
}
};
class Triangle: public Polygon
{
public:
int area ()
{
return width * height / 2;
}
};
int main()
{
Rectangle r;
Triangle t;
Polygon * ppoly1 = &r;
Polygon * ppoly2 = &t;
ppoly1->setValues (10, 50);
ppoly2->setValues (10, 25);
cout << r.area() << endl;
cout << t.area() << endl;
return 0;
}
Output: 500 125
Write a program to implement virtual function.
#include <iostream>
using namespace std;
class Polygon
{
protected:
int width, height;
public:
void setValues (int a, int b)
{
width=a;
height=b;
}
virtual int area ()
{
return (0);
}
};
class Rectangle: public Polygon
{
public:
int area ()
{
return (width * height);
}
};
class Triangle: public Polygon
{
public:
int area ()
{
return width * height / 2;
}
};
int main()
{
Rectangle r;
Triangle t;
Polygon p;
Polygon * poly1 = &r;
Polygon * poly2 = &t;
Polygon * poly3 = &p;
poly1->setValues (10,50);
poly2->setValues (20,50);
poly3->setValues (30,50);
cout<< poly1->area()<< endl;
cout<< poly2->area()<< endl;
cout<< poly3->area()<< endl;
return 0;
}
Output: 500 500 0
Program to call pure virtual function from abstract base class.
#include <iostream>
using namespace std;
class Polygon
{
protected:
int width, height;
public:
void setValues (int a, int b)
{
width = a;
height = b; }
virtual int area (void) =0;
void printarea (void)
{
cout << this->area() << endl;
}
};
class Rectangle: public Polygon
{
public:
int area (void)
{
return (width * height);
}
};
class Triangle: public Polygon
{
public:
int area (void)
{
return (width * height / 2);
}
};
int main()
{
Rectangle r;
Triangle t;
Polygon * poly1 = &r;
Polygon * poly2 = &t;
poly1->setValues (40, 50);
poly2->setValues (10, 20);
poly1->printarea();
poly2->printarea();
return 0;
}
Output: 2000 100
Write a program of abstract base class.
#include <iostream>
using namespace std;
class Polygon
{
protected:
int width, height;
public:
void setValues (int a, int b)
{
width=a;
height=b;
}
virtual int area (void) =0;
};
class Rectangle: public Polygon
{
public:
int area (void)
{
return (width * height);
}
};
class Triangle: public Polygon
{
public:
int area (void)
{
return (width * height / 2);
}
};
int main()
{
Rectangle r;
Triangle t;
Polygon * poly1 = &r;
Polygon * poly2 = &t;
poly1->setValues (40, 25);
poly2->setValues (20, 50);
cout << poly1->area() << endl;
cout << poly2->area() << endl;
return 0;
}
Output: 1000 500
Program of function template in C++.
#include <iostream>
using namespace std;
template <class T> T GetMax (T a, T b)
{
T result;
result = (a>b)? a : b;
return result;
}
int main()
{
int i = 10, j = 20, k;
long l = 10, m = 50, n;
k = GetMax<int>(i, j);
n = GetMax<long>(l, m);
cout << k << endl;
cout << n << endl;
return 0;
}
Output: 20 50
Program of class template in C++
#include <iostream>
using namespace std;
template <class T> class Pair
{
T a, b;
public:
Pair (T first, T second)
{
a=first;
b=second;
}
T getmax ();
};
template <class T> T Pair<T>::getmax ()
{
T retval;
retval = a > b? a : b;
return retval;
}
int main()
{
Pair <int> obj (200, 705);
cout << obj.getmax();
return 0;
}
Output: 705
Write a program to by using namespaces.
#include <iostream>
using namespace std;
namespace intvalue
{
int var = 100;
}
namespace doublevalue
{
double var = 10.50;
}
int main()
{
cout << intvalue::var << endl;
cout << doublevalue::var << endl;
return 0;
}
Output: 100 10.5
Program to show usage of C++ “using” keyword.
#include <iostream>
using namespace std;
namespace first
{
int x = 15;
int y = 10;
}
namespace second
{
double x = 13.141;
double y = 21.718;
}
namespace third
{
double a = 500;
double b = 803;
}
int main()
{
using first::x;
using second::y;
using namespace third;
cout << x << endl; // value of first namespace
cout << y << endl; // value of second namespace
cout << first::y << endl; // value of first namespace
cout << second::x << endl; // value of second namespace
cout << a << endl; // value of third namespace
cout << b << endl; // value of third namespace
return 0;
}
Output: 15 21.718 10 13.141 500 803
Write a program using try-catch statement exception handling in C++.
#include <iostream>
using namespace std;
int main()
{
try
{
throw 100;
}
catch (int exception)
{
cout << "An exception occurred. "<< endl;
cout << "Exception number is " << exception << endl;
}
return 0;
}
Output: An exception occurred. Exception number is 100
C++ program of standard exception handling.
#include <iostream>
#include <exception>
using namespace std;
class GeekException: public exception
{
virtual const char* what() const throw()
{
return "The exception is generated.";
}
} ex;
int main()
{
try
{
throw ex;
}
catch (exception& e)
{
cout << e.what();
}
return 0;
}
Output: The exception is generated.
Write a program of class type casting in C++.
#include <iostream>
using namespace std;
class Dummy
{
float i, j;
};
class Addition
{
public:
int result(int x, int y)
{
return x + y;
}
};
int main()
{
Dummy d;
Addition * add;
add = (Addition*) &d;
cout <<"Result: " << add->result(10, 20);
return 0;
}
Output: Result: 30
Write a program using typeid in C++.
#include <iostream>
#include <typeinfo>
using namespace std;
int main()
{
int * a, b;
int * x, *y;
a = 0;
b = 0;
x = 0;
y = 0;
if (typeid(a) != typeid(b))
{
cout << "Both are of different types.\n";
}
if (typeid(x) == typeid(y))
{
cout << "Both are of same types.";
}
return 0;
}
Output: Both are of different types. Both are of same types.
C++ Program of file operation.
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
ofstream testfile;
testfile.open ("geek.txt"); // File name
testfile << "Writing this content to a file.\n";
testfile.close();
return 0;
}
Write a program of writing on a text file.
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
ofstream testfile("geekcer.txt"); // File name
if (testfile.is_open())
{
testfile << "This is a line.\n";
testfile << "This is another line.\n";
testfile.close();
}
else
{
cout << "Unable to open file";
}
return 0;
}
Program to read a text file in C++.
geekcer.txt This is a line. This is another line.
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
int main()
{
string line;
ifstream myfile ("geekcer.txt"); // File name
if (myfile.is_open())
{
while (! myfile.eof() )
{
getline (myfile,line);
cout << line << endl;
}
myfile.close();
}
else
{
cout << "Unable to open file";
}
return 0;
}
Output: This is a line. This is another line.
Write a program find the file size.
geekcer.txt This is a line. This is another line.
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
long begin, end;
ifstream myfile ("geekcer.txt");
begin = myfile.tellg();
myfile.seekg (0, ios::end);
end = myfile.tellg();
myfile.close();
cout << "Size of file is: " << (end-begin) << " bytes.\n";
return 0;
}
Output: Size of file is: 40 bytes.
Write a program to uniquely identify a namespace with the keyword namespace.
#include <iostream>
using namespace std;
namespace first
{
int data = 10;
}
namespace second
{
double data = 5.321;
}
int main()
{
cout << first::data << endl;
cout << second::data << endl;
return 0;
}
