//Author :LearningPen
//Date : 28/9/2014
//MyBolg :http://learningpen.blogspot.com/
//Language : C++
//Tool : Dev C++
Notice:
Reference http://www.sourcecodester.com/cc/7937/c-functions-basic-mathematical-operation.html.
According to some of his code, modified by myself,I also use a class structure.
Thank you...
