Take part in running competitions in special environment. You will be one of the many participants. Everyone will have a small ladder on their backs. All of them start running at the same time. You will need to develop good speed, but be smart not to fall in holes that will appear on the way from time to time and not to run into other obstacles. You will need to collect as many logs as you can during your run. Later, you will have to build the highest ladder using these logs. Note, you can get rid of your competitors as you run.