Usually the wavelet tree is made not to support updates. I wonder what types of updates it can recieve that will still keep all its operations in $O(\log{}A)$, where $A$ is the range of values it gets. For instance the only one I found is that you can support appending or removing the element from the back of the array (on which the wavelet is built).↵
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A short tutorial for this data structure can be found [here](http://codeforces.net/blog/entry/52854), for those who are interested.
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A short tutorial for this data structure can be found [here](http://codeforces.net/blog/entry/52854), for those who are interested.
