I am talking on a paper by Alonso, Reingold, Schott. Lets play the following game. I have $n$ elements $x_1,...,x_n$, each one colored RED or BLUE. $n$ is odd. Clearly either RED or BLUE is in the majority. YOU have to determine which color is in the majority (more accurately you must produce a statement like ``$x_{17}$ is colored the same as the majority'') and can only ask questions of the form ARE $x_i$ and $x_j$ the same color? HOW MANY QUESTIONS WILL THIS TAKE? Let $v(n)$ be the number of 1's in the binary representation of $n$. We prove that \begin{enumerate} \item There is an algorithm doing this in $n-v(n)$ questions \item No algorithm does better. \end{enumerate} (This talk can be considered an advertisement for my course CMSC 752 next semester.)