  In this paper, we propose a high-speed greedy sequential algorithm for the
vertex coloring problem (VCP), based on the Wave Function Collapse algorithm,
called Wave Function Collapse Coloring (WFC-C). An iteration of this algorithm
goes through three distinct phases: vertex selection, color restriction through
wave function collapsing, and domain propagation. In effect, WFC-C propagates
color choices or "domain" restrictions beyond immediate neighbourhoods. This
heuristic, combined with a series of other greedy optimizations, allows for a
fast algorithm that prevents certain color conflicts. Through extensive
experiments, we show that WFC-C remains competitive (and occasionally better)
in terms of optimal coloring, and dramatically outperforms existing high-speed
VCP, with on average speed differences ranging from 2000 times to 16000 times,
on the most difficult instances of the DIMACS benchmark.
