test

main.tex

@@ -52,7 +52,7 @@ Let $C$ and $P$ be two given set of points such that $k=|C|$ and $n=|P|$. Define
 We repeatedly build grid for $C$ with different side length and insert points in $P$ into the grid.
 $\log n$ rebuilds, each takes $O(k)$ time. each insertion takes $O(1)$ for points in $P$... 
 
-but how can i get the approximation...
+but how can i get the approximation ?...
 
 \begin{exercise}
 Given a set $P$ of $n$ points in the plane and