Can someone please explain me what THIS code is doing. I know that it involves DFS on a tree/graph. It might also involve binary search. I want to know that in init() and lca() functions, why i and j are iterated only till 18?
We want minimum K such that pow(2,K)>= N , here N = 100000 .
1.pow(2,16) = 65536
2.pow(2,17) = 131072
3.pow(2,18) = 262144
minimum K satisfying above condition is 17.
Any number >=17 will do.