figure items inserted in ascending order degenerates to (nwhen there are no branchesthe tree becomesin effecta linked list the arrangement of data is one-dimensional instead of two-dimensional unfortunatelyas with linked listyou must now search through (on the averagehalf the items to find the one you're looking for in this situation the speed of searching is reduced to ( )instead of (lognas it is for balanced tree searching through , items in such an unbalanced tree would require an average of , comparisonswhereas for balanced tree with random insertions it requires only for presorted data you might just as well use linked list in the first place data that' only partly sorted will generate trees that are only partly unbalanced if you use the binary tree workshop applet from to attempt to generate trees with nodesyou'll see that some of them are more unbalanced than othersas shown in figure although not as bad as maximally unbalanced treethis situation is not optimal for searching times in the binary tree workshop applettrees can become partially unbalancedeven with randomly generated databecause the amount of data is so small that even short run of ordered numbers will have big effect on the tree alsoa very small or very large key value can cause an unbalanced tree by not allowing the insertion of many nodes on one side or the other of its node root of for exampleallows only two more nodes to be inserted to its left