- Undirected Graph
- Directed Graph
- Depth-First Search Algorithm DFS (9:12)
- Depth First Search Algorithm Video (3:46)
- Wikipedia article on DFS
- The left subtree of a node contains only nodes with keys less than the node’s key.
- The right subtree of a node contains only nodes with keys greater than the node’s key.
- The left and right subtree each must also be a binary search tree.
- There must be no duplicate nodes.