C++ Programming Code Examples
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Inline function that calculates the volume of a sphere
/* Inline function that calculates the volume of a sphere */
#include <iostream>
using std::cout;
using std::cin;
using std::endl;
#include <cmath>
const double PI = 3.14159;
inline double sphereVolume( const double r )
{ return 4.0 / 3.0 * PI * pow( r, 3 ); }
int main()
{
double radius;
cout << "Enter the length of the radius of your sphere: ";
cin >> radius;
cout << "Volume of sphere with radius " << radius <<
" is " << sphereVolume( radius ) << endl;
return 0;
}
#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program.
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A return statement ends the processing of the current function and returns control to the caller of the function. A value-returning function should include a return statement, containing an expression. If an expression is not given on a return statement in a function declared with a non-void return type, the compiler issues an error message. If the data type of the expression is different from the function return type, conversion of the return value takes place as if the value of the expression were assigned to an object with the same function return type.
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