Tree Traversal

Here I will try to post some coding questions which can be see during interviews, but I will not be posting their answers & will be assuming that the visitors to this page will provide the solutions as per their understanding or even can discuss around that.
It will be kind of open forum for the people to post their queries, doubts, suggestions or solutions for others.

Question 1 : Below another interesting Question around Tree processing is given -
                      Suppose you have a tree of nodes like shown & now you need to print the
                      values in that tree in circular way.
Example : For below given tree, output must be -
                  A | K L | C B | H I J | G F E D