ETH Zurich, Computer Science, Zurich, Switzerland. skuncan@inf.ethz.ch|ETH Zurich, Computer Science, Zurich, Switzerland. skuncan@inf.ethz.ch|ETH Zurich, Computer Science, Zurich, Switzerland. skuncan@inf.ethz.ch|ETH Zurich, Computer Science, Zurich, Switzerland. skuncan@inf.ethz.ch|ETH Zurich, Computer Science, Zurich, Switzerland. skuncan@inf.ethz.ch|ETH Zurich, Computer Science, Zurich, Switzerland. skuncan@inf.ethz.ch|ETH Zurich, Computer Science, Zurich, Switzerland. skuncan@inf.ethz.ch