C++ program to find factorial of number using function

What are Functions ?

Function is a block of statements that performs some operations. All C++ programs have at least one function – function called “main()”. This function is entry-point of your program.

A function declaration tells the compiler about a function’s name, return type, and parameters. A function definition provides the actual body of the function.

Defining a Function : :

The general form of a C++ function definition is as follows:

return_type Function_Name( list of parameters )
{
//function’s body
}

• return_type : suggests what the function will return. It can be void, int, char, some pointer or even a class object.
• Function_Name : is the name of the function, using the function name it is called.
• Parameters : are variables to hold values of arguments passed while function is called. A function may or may not contain parameter list.
• Function body : is he part where the code statements are written.

Below is the source code for C++ program to find factorial of number using function which is successfully compiled and run on Windows System to produce desired output as shown below :

SOURCE CODE : :

/*  C++ program to find factorial of number using function  */

#include<iostream>
using namespace std;

void factorial(int);

int main()
{
        int n;
        cout<<"Enter any number :: ";
        cin>>n;
        factorial(n);

}

void factorial(int n)
{
        int f=1,n1;
        n1=n;
        if(n==0)
        cout<<"\nFactorial of [ "<<n1<<"! ] is 1.\n";
        else
        {
                while(n>0)
                {
                        f=f*n;
                        n--;
                }
        }
        cout<<"\nFactorial of [ "<<n1<<"! ] is "<<f<<"\n";

}

OUTPUT : :

/*  C++ program to find factorial of number using function  */

Enter any number :: 7

Factorial of [ 7! ] is 5040

Process returned 0

Above is the source code for C++ program to find factorial of number using function which is successfully compiled and run on Windows System.The Output of the program is shown above .