Postcards#164
Valentine's Day was approaching. Masha and her friends decided to celebrate by making postcards. To decorate the postcards, Masha used circles of different sizes and a decorative ribbon. The process of making a postcard is as follows: first, circles are placed onto a cardboard base; then, a ribbon is glued along the perimeter of the resulting figure (or figures, as there may be several), so as to fully cover all the joints of the circles with the cardboard. To do this, Masha needs to determine the length of ribbon required to decorate one postcard. Help her.
The input consists of several lines, each describing a circle with three real numbers: , , and , separated by spaces (-10 \le x, y \le 10, 0.001 \le r \le 10), each given with decimal places of precision. The number of lines is between and .
Output a single number — the total length of ribbon required to decorate the postcard. The answer should be given in fixed-point format with exactly decimal places.
Example 1