You are given parallelepiped with length \textbf{A}, width \textbf{B} and height \textbf{C}. Find surface distance to the most distant (by surface) point from vertex of parallelepiped. \InputFile The only line has three integers \textbf{A}, \textbf{B}, \textbf{C}. \OutputFile The only real number is distance with absolute or relative error no greater than \textbf{10^\{-8\}}. \textbf{Limits} \textbf{1} ≤ \textbf{A}, \textbf{B}, \textbf{C} ≤ \textbf{1000}