Peter cuts the cardboard into circle and triangle, and Vassya tries to impose them on each other to obtain such a position, in which area of overlapping \textbf{2} pieces will be maximised. Help Vassya. \InputFile The first line specifies the number of pairs of figures \textbf{T}, Petya cut (\textbf{1 }≤ \textbf{T }≤ \textbf{20}), and the subsequent \textbf{T} rows of four integers through the gap: the length of the triangle sides \textbf{a}, \textbf{b}, \textbf{c} and the radius of the circle \textbf{R}. \textbf{(1} ≤ \textbf{a }≤ \textbf{b }≤ \textbf{c} ≤ \textbf{100}, \textbf{1} ≤ \textbf{R} ≤ \textbf{100, a+b>c}) \OutputFile Output \textbf{T} numbers found Vassya (one per line). Bring out the results with an accuracy of \textbf{2} digits after the decimal point.