(235)Lowest Common Ancestor

Lowest Common Ancestor
Approach :1
i)This question seems to be primitve and of lower difficulty which it actually is as the implementation behind is a cake walk but the keen eye of frisking the logic out of this tree structure is what baffled me at the beginning.
ii)The code I had written was skipping over the root so I was unable to pass thosw testcases in which the root was the lowest common ancestor as I was passing the root.left and root.right sperately for the calls to helper function and in most of the cases the root was the common ancestor.
iii)Later after contemplating about this question , there are only two ways in which the common ancestor can be different than the root and those are :
        ~)As the two nodes have been given and the node let's say p is found in left subtree and the recursion returns and q is not found in right subtree which just means 
        that the q is present in left subtree below the p node . Vice Versa of above is also true for q being found in the right subtree but recursion in left subtree returns 
        without p node.
        ~)For the above mentioned case just return the found node whichever is found whether in the left or right subtree as that is the lowest common ancestor .
        ~)If both the q and p nodes are found in right and left subtree resp. then the root is the Lowest Common Ancestor.

iv)That is how I implemented this code without exhausting much of my time and still coming up with a robust solution.

Overall : This was a pretty good question as it required some of my observation skills and little patience for evaluating the correct approach . The worst part and the most significant too is the cases which I thought of later .