Introduction to Tree Depth-First Search
Explore the tree depth-first search pattern to understand how preorder, inorder, and postorder traversals work for exploring binary trees. Learn to apply this method for tasks like path sums and validating binary search trees. This lesson helps you master efficient tree traversal techniques useful in coding interviews and real-world problems.
About the pattern
A tree is a graph that contains the following properties:
It is
undirected A graph with edges that do not have a specific direction assigned to them. It is
acyclic A graph without cycles. It is a connected graph where any two vertices are connected by exactly one path.
Its nodes can contain values of any data type.
The following key features set trees apart from other data structures, such as arrays or linked lists:
They organize data in a hierarchical manner with a root node at the top and child nodes branching out from it.
They are nonlinear, which means that the elements in a tree are not arranged sequentially but rather in a branching structure.
The time complexity for search and insert operations in trees is typically
, where ...