Had anyone solved Day6 part1 with something more e...

# advent-of-code

[ilya.gorbunov]

Had anyone solved Day6 part1 with something more elaborate than brute force? I suppose it has O(maxX*maxY*numerOfSites) complexity to find the nearest site in each point of the field.
On the other hand the field can be filled with a number of simultaneous breadth-first searches starting at locations of the sites, that would require O(maxX*maxY) operations. Something like this Voronoi diagram, but just for manhattan distance:

https://upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Voronoi_growth_euclidean.gif/220px-Voronoi_growth_euclidean.gif▾