Hello all,

Today I will bring you some interesting problem: Oh, I forgot to mention I cannot solve it...Dx

So here is the problem. I guess I have some observation: that we have to consider the cycles in the graph. For example, in this graph here, we have 4 regions, and each region has an edge the other regions don't use. (Regions are coloured)

However, if I put new node 9 here, and try to colour like this:

But look it the problem here: if we try to use all 3 blue loops, then we cannot use the orange loop. So there is something tricky here.

So if anyone has any ideas or can provide some hints, I would really appreciate!

Thanks,

minimario

(P.S. If anyone want to continue solving Timus problem with me starting from 1077 and going down by difficulty, send me a message :))