Calculate the total surface area of a truncated cone, if we know the base radius \textbf{R}, \textbf{r} and height \textbf{h}. \InputFile In a single line of succession through a gap defined, respectively, the base radius \textbf{R}, \textbf{r} and height \textbf{h}. All input data are integers, not exceeding \textbf{100}. \OutputFile In a single line to bring the total surface area of a truncated cone. Result output to two decimal places.