When you write a function to solve a task, you may break the task into subtasks. Sometimes, one of the subtasks is a smaller version of the same task and can be accomplished by calling itself multiple times. In such cases the function is said to be recursive.

Write a recursive function to calculate the value of n$!.$ Factorial of a number is defined as: n$!=$ n$($n$-1)($n$-2)($n$-3)...(2)(1).$ For example, $4!=4*3*2*1.$ The n$!$ can be written in terms of $($n$-1)!$ as: n$!=$ n$*($n$-1)!,($n$-1)!=($n$-1)*($n$-2)!$ and so forth.

Thus, in order to compute n$!,$ we need $($n$-1)!,$ to have $($n$-1)!,$ we need $($n$-2)!$ and so forth. As you may immediately notice, the base case for factorial is $1$ because $1!=1.$ Write a program that uses a recursive function called factorial that takes an integer n as its argument and returns n$!$ to the main.

Sample Output: Red colored texts are user inputs. Other texts are the output of the program.

Enter the number: $4$

The factorial of the number is $24.$