Lucca, my four-years-old daughter, loves drawing polygons in bond paper. For example, yesterday she drew two squares, a rectangle and two triangles: \includegraphics{https://static.e-olymp.com/content/17/17cbdc9a41665da6e51b7b0acfff81fdaea25b6b.jpg} Today, she wanted to fill her figures with black chinese ink. I helped her, obtaining the next result: \includegraphics{https://static.e-olymp.com/content/28/28ad7a68f6ee2ec673798a19ce4366f9b22145de.jpg} She asked me: how many black zones do you see?. I said: two. I'm bored answering the same question everyday. Can you help us writing a program that, given a collection of black filled polygons, determines the number of black zones on the drawing? For a precise understanding: a \textit{black zone} is a region of black coloured points on the sheet, where every pair of them may be connected by a continuous line within the region. \InputFile The input consists of several test cases. Each test case is represented as follows: \begin{itemize} \item A line with an integer \textbf{N} (\textbf{1} ≤ \textbf{N} ≤ \textbf{40}) which indicates the number of polygons in the drawing. \item \textbf{N} lines, one per polygon, each one containing a list of \textbf{2·t} integer numbers \textbf{x_1} \textbf{y_1 x_2 y_2 ... x_t y_t} specifying the points in the boundary of the polygon (\textbf{-10^4} ≤ \textbf{x_i}, \textbf{y_i} ≤ \textbf{10^4}, \textbf{3} ≤ \textbf{t} ≤ \textbf{10}). The drawn polygon is bounded by the closed path composed of the straight line segments \includegraphics{http://uva.onlinejudge.org/external/116/11665img4.png} , \includegraphics{http://uva.onlinejudge.org/external/116/11665img5.png} , ..., \includegraphics{http://uva.onlinejudge.org/external/116/11665img6.png} , and \includegraphics{http://uva.onlinejudge.org/external/116/11665img7.png} . You can suppose that the drawn polygon is a simple polygon (a polygon whose boundary is a non-self-intersecting closed path). \end{itemize} The end of the input is indicated when \textbf{N} = \textbf{0}. \OutputFile For each case in the input, print one line with the number of black zones in the drawing after filling each one of the polygons with black chinese ink.