Chapter 9 · SimulationGeneral Tree Simulator ? ← Chapter 9 Node label Add child Select root Delete subtree Ancestors Descendants DFS preorder BFS level order Load example Clear highlights Stop Click a node to select it. Close General Tree Simulator A rooted tree in which a node may have any number of children. Click a node to select it; every operation acts on the selected node. Controls Add child hangs a new node with the given label under the selected node (12 nodes at most). Select root selects the root. Delete subtree removes the selected node together with all its descendants. Ancestors highlights the path up to the root; Descendants highlights the whole subtree. DFS preorder and BFS level order animate the two traversals. Stop interrupts an animation, Clear highlights removes the colors, and Load example brings back the sample tree. Terms A leaf is a node with no children. The degree of a node is its number of children. The depth of a node is the number of edges from the root to it; the height of the tree is the largest depth. In the Selected box, d is the depth and deg the degree. Traversals Preorder DFS visits a node first and then its subtrees from left to right. The orange edges trace the current recursion path down from the root. BFS uses a queue: dequeue the front node, enqueue its children, and the tree is visited level by level. Both traversals visit every node exactly once, so each takes O(n) time.