24 Feb
2012
24 Feb
'12
2:38 a.m.
Hello,
Looking at IntMap's left-biased 'union' function [1], I noticed that the complexity is O(n+m) where n is the size of the left map, and m is the size of the right map.
Since insertion [2] is O(min(n, W)) [ where W is the number of bits in an Int ], wouldn't it be more efficient to just fold 'insert' over one of the lists for a complexity of O(m*min(n, W))? This would degrade into O(m) in the worst case, as opposed to the current O(n+m).
Interesting. I would point out that the original paper "Fast Mergeable Integer Maps" says that merge is O(n+m). I don't know which one is correct. --Kazu