Exact Bounds for Distributed Graph Colouring
نویسندگان
چکیده
We prove exact bounds on the time complexity of distributed graph colouring. If we are given a directed path that is properly coloured with n colours, by prior work it is known that we can find a proper 3-colouring in 12 log ∗(n) ± O(1) communication rounds. We close the gap between upper and lower bounds: we show that for infinitely many n the time complexity is precisely 12 log ∗ n communication rounds. ar X iv :1 50 2. 04 96 3v 2 [ cs .D C ] 2 6 Fe b 20 15
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