I am trying to build a scientific calculator. However, I have two major problems.

1. The decimal to separate the tens from the tenth

2. Modulus which outputs the remainder of the division of two numbers.

Remainder = dividend – quotient * divisor;

I can get the rest, but I am having problems on how to input these into programming. If anyone knows how to use this for Visual C++.net, please help. Also, I am using GUI (Graphics User Interface). I am suppose to build a modulus button.