This is a simple Calculator developed using Java Servlets, so it uses the form type in html & uses regex for validating the numerical values.
Have you heard of Roger Bannister? He was the first athlete to run the mile in less than four minutes.
It’s important to understand that our achievements in life are limited not by what we can do, but by what we think we can do. More than ability, it’s our attitude that makes the difference. As Henry Ford said, “If you think you can, you can. And if you think you can’t, you are right”.