Computational Thinking Steps in Solving Bebras Challenges: Part 2

 

When I employed problem decomposition, I found that, to solve the “Traffic in the City” challenge, I needed to first determine why each square in the sample chart was checked, filled, or blank, and after figuring that out I would then complete the challenge by filling in the larger square using the same methodology as the first square. I then looked for patterns in the checked, filled and blank boxes, and noticed that the boxes, each coordinated with two points on the map, were checked if the taxi could move from one of the points to the other without crossing through any other points, and blank if the taxi could not. Based on these observations, I formed an abstract model; when the taxi could move straight from one point to another without passing through any other points, the box where these two points met on the chart was checked, and when the taxi could not move from one point to another without moving through any other points, the box was blank. So, algorithmically, I could follow a few steps to fill any box on the chart; find a box on the chart, identify the two points it coordinated with, check the map to see if the taxi could move between those points in a straight shot, and then place a check in the box if the taxi could or leave it blank if the taxi could not.