It's a console based application to find factorial of any integer number and it is based on a concept of Tail call optimisation. It allows you to get factorial until you press Q/q to exit. The app is capable to calculate factorial of any large number and will never give any stack overflow error. If the answer is out of range, then it will return Infinity.

• Install dependencies. Run npm install.
• Once dependencies installed then, Run npm start.

Run npm test.

StackOverFlow : Tail-call optimization is where you are able to avoid allocating a new stack frame for a function because the calling function will simply return the value that it gets from the called function. The most common use is tail-recursion, where a recursive function written to take advantage of tail-call optimization can use constant stack space. As per Wikipedia In computer science, a tail call is a subroutine call performed as the final action of a procedure. If a tail call might lead to the same subroutine being called again later in the call chain, the subroutine is said to be tail-recursive, which is a special case of recursion. Tail recursion (or tail-end recursion) is particularly useful, and often easy to handle in implementations.