Description
Please implement a web service which calculates and displays results for the following
algorithms:
- Calculating a Fibonacci number F(n) with the value of n provided by the user.
- The Ackermann function A(m,n) with values of m and n provided by the user.
- The factorial of a non-negative integer n provided by the user.
The results per function should be calculated separately and user’s input should be
validated.