Interactive DSA and system design

Learn complex engineering ideas by watching them move.

37stepsO(n)averageO(h)space

Trees lab

DFS Pre/In/Postorder Traversals

Step 1 / 37

Traversal Output Trace

Empty

Comparing Node Active / Traversed Node Inserted Duplicate / Match

Animation speed

Space play / pause←→ stepR reset

Current operation

Initialize Inorder Traversal

We start traversing the binary tree from the Root node. Output list is empty.

Algorithm state

InorderTraversal TypeNoneCurrent NodeEmptyOutput List

Select Traversal Type

Choose Preorder (Root-L-R), Inorder (L-Root-R), or Postorder (L-R-Root).

Complexity notes

O(n)averageO(n)worstO(h)spaceN/Astable

Synced code trace

function traverse(node) {  if (node === null) return;  // Preorder: visit(node)  traverse(node.left);  // Inorder: visit(node)  traverse(node.right);  // Postorder: visit(node)}

Interactive Notes

✓ Notes are saved automatically and persist per step.