C++ program to find the factorial of the number

In this chapter of C++ program tutorial out task is: 

• Write a C++ program to find the factorial of a number

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C++ program to find the factorial of a number

Below is the C++ program to find factorial of a number.

#include<iostream>
using namespace std;
void factorial(int n){
    int fact = 1,i;
    for(i=1;i<=n;i++){
        fact = fact * i;
    }
    cout<<"The factorial of "<<n<<" is "<<fact;
}
int main()
{
    int n;
    cout<<"Enter the number to calculate the factorial\n";
    cin>>n;
    factorial(n);
    return 0;
}

OUTPUT :

Enter the number to calculate the factorial

• The execution starts from the main function (here int main()).
• A 4-bit memory space is allocated to the integer n.
• Then the integer "n" is taken as the input 
• Then the fuction factorial is called by passing the value of "n".
• The facorial function is calculated and the required output is displayed.
• The program then terminates in the line "return 0" returning a 0 value.

WORKING :

The working is for the factorial function.

let n = 5

for(i=1;i<=5;i++)

1st iteration:

fact = fact * i  // fact =1 * 1 = 1  and i=2

2nd iteration:

fact = fact * i  // fact =1 * 2 = 2  and i=3

3rd iteration:

fact = fact * i  // fact =2 * 3 = 6  and i=4

4th iteration:

fact = fact * i  // fact =6 * 4 = 24  and i=5

5th iteration:

fact = fact * i  // fact =24 * 5 = 120  and i=6

And after this i=6 which is a false condition and the loop terminates

 

You can see the above code execution and output in codeblocks IDE: