Wet, Wet, Wet | Australian Maths Trust

Wet, Wet, Wet

This blog post accounts for the highlights of the Australian IOI team’s third day of training at the pre-departure camp at UNSW Sydney, as told by IOI team member Ryan Wang. Ryan is representing Australia at the IOI for the first time this year, and is the first Australian Capital Territory student in 11 years to be selected to the Australian team.

You cannot feel your fingers. You cannot feel your toes. The rain is all around you, and so the river flows. We were all proud of Tunan for being able to recite the first few sentences of the problem “Wet, Wet, Wet” in the rain. While he continued memorising the flavour text [Ed. the thematic story] of the problem, I was chosen as the blogger for today. Welp, Tunan is now asking me to talk about other people.

Today’s game to choose the blogger involved us finding the largest clique in the graph [Ed. the graph should be treated as undirected, despite the arrowheads] pictured below, in three minutes.

As promised, a video of the students’ game!
The students after the latest edition of their blog-deciding informatics-themed game.

A clique is a part of the graph where every vertex has an edge to every other vertex [Ed. or a group of people among whom every pair are friends with each other]. Having missed a curved edge (1->8) hidden among the mesh, I lost the game and became the designated blogger.

CEOI day 2 was the trial exam for today. The problems were interesting and more difficult than those in the previous trial exams.

After the trial exam we, had our customary frisbee session. This time, we had a person in the middle of the cycle / circle trying to fail the others and replace them. Turns out if you are in the middle, standing right in front of the person with the frisbee almost worked every time.

After dinner, Josh attempted to explain tree decomposition to us and all of us except Angus (who already knew the topic) decided it might be better for us to read the Wikipedia page instead.