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Generalmarkus41

data-structures

Computer science data structure visualization in draw.io — arrays, linked lists, trees, graphs, hash tables, heaps, stacks, queues

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12
Source
markus41/claude
Updated
2026-05-11
Slug
markus41--claude--data-structures
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Data Structure Diagrams

Quick Reference

Structure Best For Complexity
Array Sequential data, index access Low
Linked List Insertion/deletion demos Low
Stack LIFO operations, call stacks Low
Queue FIFO operations, BFS Low
Binary Tree Hierarchical data, BST Medium
AVL / Red-Black Tree Balanced search demos Medium
B-Tree Database index visualization High
Heap Priority queue, heapsort Medium
Hash Table Key-value mapping, collisions Medium
Graph Networks, relationships, paths Medium-High
Trie Prefix search, autocomplete Medium

Shared Style Constants

Cell colors:
  Default:    fillColor=#DAE8FC;strokeColor=#6C8EBF;  (blue)
  Highlight:  fillColor=#D5E8D4;strokeColor=#82B366;  (green — active/found)
  Alert:      fillColor=#F8CECC;strokeColor=#B85450;  (red — removed/error)
  Visited:    fillColor=#FFF2CC;strokeColor=#D6B656;  (yellow — traversed)
  Empty:      fillColor=#F5F5F5;strokeColor=#CCCCCC;  (gray — null/empty)

Text:  fontColor=#333333;fontSize=14;fontFamily=Consolas;
Index: fontColor=#999999;fontSize=10;fontStyle=2;  (italic, small)
Arrow: strokeColor=#666666;strokeWidth=2;endArrow=block;endFill=1;

Arrays

Linear Array

<mxGraphModel>
  <root>
    <mxCell id="0"/>
    <mxCell id="1" parent="0"/>
    <!-- Index labels -->
    <mxCell id="idx0" value="0" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#999999;fontSize=10;fontStyle=2;align=center;" vertex="1" parent="1">
      <mxGeometry x="40" y="20" width="60" height="20" as="geometry"/>
    </mxCell>
    <mxCell id="idx1" value="1" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#999999;fontSize=10;fontStyle=2;align=center;" vertex="1" parent="1">
      <mxGeometry x="100" y="20" width="60" height="20" as="geometry"/>
    </mxCell>
    <mxCell id="idx2" value="2" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#999999;fontSize=10;fontStyle=2;align=center;" vertex="1" parent="1">
      <mxGeometry x="160" y="20" width="60" height="20" as="geometry"/>
    </mxCell>
    <mxCell id="idx3" value="3" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#999999;fontSize=10;fontStyle=2;align=center;" vertex="1" parent="1">
      <mxGeometry x="220" y="20" width="60" height="20" as="geometry"/>
    </mxCell>
    <mxCell id="idx4" value="4" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#999999;fontSize=10;fontStyle=2;align=center;" vertex="1" parent="1">
      <mxGeometry x="280" y="20" width="60" height="20" as="geometry"/>
    </mxCell>
    <!-- Array cells -->
    <mxCell id="a0" value="42" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontColor=#333333;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="40" y="40" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="a1" value="17" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontColor=#333333;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="100" y="40" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="a2" value="93" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#D5E8D4;strokeColor=#82B366;fontColor=#333333;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="160" y="40" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="a3" value="8" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontColor=#333333;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="220" y="40" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="a4" value="51" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontColor=#333333;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="280" y="40" width="60" height="40" as="geometry"/>
    </mxCell>
    <!-- Pointer arrow -->
    <mxCell id="ptr" value="current" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#B85450;fontSize=11;fontStyle=1;align=center;" vertex="1" parent="1">
      <mxGeometry x="160" y="90" width="60" height="20" as="geometry"/>
    </mxCell>
  </root>
</mxGraphModel>

2D Matrix

Use a grid of cells. Each row shares the same Y, each column the same X. Add row/column headers with index labels.

<!-- Row 0 -->
<mxCell id="m00" value="1" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=13;fontFamily=Consolas;" vertex="1" parent="1">
  <mxGeometry x="80" y="40" width="50" height="40" as="geometry"/>
</mxCell>
<mxCell id="m01" value="2" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=13;fontFamily=Consolas;" vertex="1" parent="1">
  <mxGeometry x="130" y="40" width="50" height="40" as="geometry"/>
</mxCell>
<mxCell id="m02" value="3" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=13;fontFamily=Consolas;" vertex="1" parent="1">
  <mxGeometry x="180" y="40" width="50" height="40" as="geometry"/>
</mxCell>
<!-- Row 1 -->
<mxCell id="m10" value="4" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=13;fontFamily=Consolas;" vertex="1" parent="1">
  <mxGeometry x="80" y="80" width="50" height="40" as="geometry"/>
</mxCell>

Linked Lists

Singly Linked List

Each node has a data cell and a pointer cell side by side:

<mxGraphModel>
  <root>
    <mxCell id="0"/>
    <mxCell id="1" parent="0"/>
    <!-- Node 1 -->
    <mxCell id="n1data" value="10" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="40" y="60" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="n1ptr" value="&#x2022;" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=18;" vertex="1" parent="1">
      <mxGeometry x="100" y="60" width="30" height="40" as="geometry"/>
    </mxCell>
    <!-- Node 2 -->
    <mxCell id="n2data" value="20" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="200" y="60" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="n2ptr" value="&#x2022;" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=18;" vertex="1" parent="1">
      <mxGeometry x="260" y="60" width="30" height="40" as="geometry"/>
    </mxCell>
    <!-- Node 3 (tail) -->
    <mxCell id="n3data" value="30" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="360" y="60" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="n3ptr" value="&#x2205;" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#F5F5F5;strokeColor=#CCCCCC;fontSize=14;" vertex="1" parent="1">
      <mxGeometry x="420" y="60" width="30" height="40" as="geometry"/>
    </mxCell>
    <!-- Arrows -->
    <mxCell id="e12" style="edgeStyle=entityRelationEdgeStyle;strokeColor=#666666;strokeWidth=2;endArrow=block;endFill=1;" edge="1" source="n1ptr" target="n2data" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="e23" style="edgeStyle=entityRelationEdgeStyle;strokeColor=#666666;strokeWidth=2;endArrow=block;endFill=1;" edge="1" source="n2ptr" target="n3data" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <!-- Head label -->
    <mxCell id="head" value="head" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#B85450;fontSize=11;fontStyle=1;align=center;" vertex="1" parent="1">
      <mxGeometry x="40" y="36" width="60" height="20" as="geometry"/>
    </mxCell>
  </root>
</mxGraphModel>

Doubly Linked List

Same as above but add a second pointer cell on the left of each node, and backward arrows.

Stacks and Queues

Stack (LIFO)

Vertical arrangement, top item highlighted:

<mxGraphModel>
  <root>
    <mxCell id="0"/>
    <mxCell id="1" parent="0"/>
    <mxCell id="sLabel" value="&lt;b&gt;Stack&lt;/b&gt;" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#333333;fontSize=16;align=center;" vertex="1" parent="1">
      <mxGeometry x="60" y="10" width="80" height="24" as="geometry"/>
    </mxCell>
    <!-- Top (most recent push) -->
    <mxCell id="s3" value="&lt;b&gt;C&lt;/b&gt;  ← top" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#D5E8D4;strokeColor=#82B366;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="40" y="40" width="120" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="s2" value="B" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="40" y="80" width="120" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="s1" value="A" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="40" y="120" width="120" height="40" as="geometry"/>
    </mxCell>
  </root>
</mxGraphModel>

Queue (FIFO)

Horizontal arrangement with front/rear labels:

<mxGraphModel>
  <root>
    <mxCell id="0"/>
    <mxCell id="1" parent="0"/>
    <mxCell id="front" value="front →" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#B85450;fontSize=11;fontStyle=1;align=right;" vertex="1" parent="1">
      <mxGeometry x="0" y="48" width="55" height="24" as="geometry"/>
    </mxCell>
    <mxCell id="q1" value="A" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#D5E8D4;strokeColor=#82B366;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="60" y="40" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="q2" value="B" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="120" y="40" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="q3" value="C" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="180" y="40" width="60" height="40" as="geometry"/>
    </mxCell>
    <mxCell id="rear" value="← rear" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#B85450;fontSize=11;fontStyle=1;align=left;" vertex="1" parent="1">
      <mxGeometry x="245" y="48" width="55" height="24" as="geometry"/>
    </mxCell>
  </root>
</mxGraphModel>

Binary Trees

Binary Search Tree

<mxGraphModel>
  <root>
    <mxCell id="0"/>
    <mxCell id="1" parent="0"/>
    <!-- Root -->
    <mxCell id="n8" value="8" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="260" y="40" width="50" height="50" as="geometry"/>
    </mxCell>
    <!-- Level 1 -->
    <mxCell id="n3" value="3" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="140" y="130" width="50" height="50" as="geometry"/>
    </mxCell>
    <mxCell id="n10" value="10" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="380" y="130" width="50" height="50" as="geometry"/>
    </mxCell>
    <!-- Level 2 -->
    <mxCell id="n1" value="1" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="80" y="220" width="50" height="50" as="geometry"/>
    </mxCell>
    <mxCell id="n6" value="6" style="ellipse;whiteSpace=wrap;html=1;fillColor=#D5E8D4;strokeColor=#82B366;fontSize=16;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="200" y="220" width="50" height="50" as="geometry"/>
    </mxCell>
    <mxCell id="n14" value="14" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="440" y="220" width="50" height="50" as="geometry"/>
    </mxCell>
    <!-- Edges -->
    <mxCell id="e1" style="strokeColor=#666666;strokeWidth=2;endArrow=none;" edge="1" source="n8" target="n3" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="e2" style="strokeColor=#666666;strokeWidth=2;endArrow=none;" edge="1" source="n8" target="n10" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="e3" style="strokeColor=#666666;strokeWidth=2;endArrow=none;" edge="1" source="n3" target="n1" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="e4" style="strokeColor=#666666;strokeWidth=2;endArrow=none;" edge="1" source="n3" target="n6" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="e5" style="strokeColor=#666666;strokeWidth=2;endArrow=none;" edge="1" source="n10" target="n14" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
  </root>
</mxGraphModel>

Node Style Variants

Type Style Use
Default node ellipse;fillColor=#DAE8FC;strokeColor=#6C8EBF; Unvisited
Current / found ellipse;fillColor=#D5E8D4;strokeColor=#82B366; Highlight during traversal
Removed ellipse;fillColor=#F8CECC;strokeColor=#B85450;dashed=1; Deleted node
Null leaf ellipse;fillColor=#F5F5F5;strokeColor=#CCCCCC;fontColor=#CCCCCC; NIL sentinel

AVL Tree Annotations

Add balance factor as a superscript label above each node:

<mxCell id="bf" value="bf=+1" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#999999;fontSize=9;align=center;" vertex="1" parent="1">
  <mxGeometry x="250" y="24" width="70" height="16" as="geometry"/>
</mxCell>

Heaps

Min-Heap (Array-backed tree)

Show both the tree view and the underlying array. Use the same node IDs so the relationship is clear.

Tree layout is identical to BST above. Below the tree, add the array view:

<!-- Array representation -->
<mxCell id="arrLabel" value="&lt;b&gt;Array:&lt;/b&gt;" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#333;fontSize=12;align=right;" vertex="1" parent="1">
  <mxGeometry x="0" y="320" width="60" height="30" as="geometry"/>
</mxCell>
<mxCell id="h0" value="1" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#D5E8D4;strokeColor=#82B366;fontSize=13;fontFamily=Consolas;" vertex="1" parent="1">
  <mxGeometry x="70" y="320" width="45" height="30" as="geometry"/>
</mxCell>
<mxCell id="h1" value="3" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=13;fontFamily=Consolas;" vertex="1" parent="1">
  <mxGeometry x="115" y="320" width="45" height="30" as="geometry"/>
</mxCell>
<mxCell id="h2" value="5" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=13;fontFamily=Consolas;" vertex="1" parent="1">
  <mxGeometry x="160" y="320" width="45" height="30" as="geometry"/>
</mxCell>

Hash Tables

Separate Chaining

<mxGraphModel>
  <root>
    <mxCell id="0"/>
    <mxCell id="1" parent="0"/>
    <mxCell id="title" value="&lt;b&gt;Hash Table (size=5, separate chaining)&lt;/b&gt;" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#333;fontSize=14;align=left;" vertex="1" parent="1">
      <mxGeometry x="20" y="10" width="400" height="24" as="geometry"/>
    </mxCell>
    <!-- Bucket 0 -->
    <mxCell id="b0" value="[0]" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#E6E6E6;strokeColor=#999999;fontSize=13;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="20" y="50" width="60" height="36" as="geometry"/>
    </mxCell>
    <mxCell id="b0n1" value="&quot;apple&quot;" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=12;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="120" y="50" width="80" height="36" as="geometry"/>
    </mxCell>
    <mxCell id="b0e1" style="strokeColor=#666;strokeWidth=1;endArrow=block;endFill=1;" edge="1" source="b0" target="b0n1" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <!-- Bucket 1 (empty) -->
    <mxCell id="b1" value="[1]" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#E6E6E6;strokeColor=#999999;fontSize=13;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="20" y="96" width="60" height="36" as="geometry"/>
    </mxCell>
    <mxCell id="b1null" value="null" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#CCCCCC;fontSize=11;fontFamily=Consolas;fontStyle=2;" vertex="1" parent="1">
      <mxGeometry x="120" y="104" width="40" height="20" as="geometry"/>
    </mxCell>
    <!-- Bucket 2 (chain of 2) -->
    <mxCell id="b2" value="[2]" style="rounded=0;whiteSpace=wrap;html=1;fillColor=#E6E6E6;strokeColor=#999999;fontSize=13;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="20" y="142" width="60" height="36" as="geometry"/>
    </mxCell>
    <mxCell id="b2n1" value="&quot;banana&quot;" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=12;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="120" y="142" width="80" height="36" as="geometry"/>
    </mxCell>
    <mxCell id="b2n2" value="&quot;grape&quot;" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#FFF2CC;strokeColor=#D6B656;fontSize=12;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="240" y="142" width="80" height="36" as="geometry"/>
    </mxCell>
    <mxCell id="b2e1" style="strokeColor=#666;strokeWidth=1;endArrow=block;endFill=1;" edge="1" source="b2" target="b2n1" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="b2e2" style="strokeColor=#666;strokeWidth=1;endArrow=block;endFill=1;" edge="1" source="b2n1" target="b2n2" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
  </root>
</mxGraphModel>

Open Addressing (Linear Probing)

Use a single row of cells (like an array) with color coding:

Color Meaning
Blue (#DAE8FC) Occupied — hashed to this index
Yellow (#FFF2CC) Occupied — probed to this index (collision)
Gray (#F5F5F5) Empty slot
Red (#F8CECC) Tombstone (deleted)

Graphs

Directed Graph (Adjacency Visualization)

<mxGraphModel>
  <root>
    <mxCell id="0"/>
    <mxCell id="1" parent="0"/>
    <!-- Vertices -->
    <mxCell id="vA" value="A" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="200" y="40" width="50" height="50" as="geometry"/>
    </mxCell>
    <mxCell id="vB" value="B" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="80" y="160" width="50" height="50" as="geometry"/>
    </mxCell>
    <mxCell id="vC" value="C" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="320" y="160" width="50" height="50" as="geometry"/>
    </mxCell>
    <mxCell id="vD" value="D" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=16;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="200" y="280" width="50" height="50" as="geometry"/>
    </mxCell>
    <!-- Directed edges with weights -->
    <mxCell id="eAB" value="4" style="strokeColor=#666666;strokeWidth=2;endArrow=block;endFill=1;fontColor=#B85450;fontSize=11;fontStyle=1;" edge="1" source="vA" target="vB" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="eAC" value="2" style="strokeColor=#666666;strokeWidth=2;endArrow=block;endFill=1;fontColor=#B85450;fontSize=11;fontStyle=1;" edge="1" source="vA" target="vC" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="eBD" value="3" style="strokeColor=#666666;strokeWidth=2;endArrow=block;endFill=1;fontColor=#B85450;fontSize=11;fontStyle=1;" edge="1" source="vB" target="vD" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="eCD" value="1" style="strokeColor=#666666;strokeWidth=2;endArrow=block;endFill=1;fontColor=#B85450;fontSize=11;fontStyle=1;" edge="1" source="vC" target="vD" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
  </root>
</mxGraphModel>

Undirected Graph

Same as directed but use endArrow=none;startArrow=none; on edges.

Graph Traversal Coloring

Show BFS/DFS state with node colors:

State Fill Meaning
Unvisited #DAE8FC (blue) Not yet discovered
In queue/stack #FFF2CC (yellow) Discovered, not processed
Processing #D5E8D4 (green) Currently visiting
Completed #E6E6E6 (gray) Fully processed

Tries

Prefix Trie

<mxGraphModel>
  <root>
    <mxCell id="0"/>
    <mxCell id="1" parent="0"/>
    <!-- Root -->
    <mxCell id="root" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#E6E6E6;strokeColor=#999;fontSize=12;" vertex="1" parent="1">
      <mxGeometry x="200" y="20" width="30" height="30" as="geometry"/>
    </mxCell>
    <!-- Level 1 -->
    <mxCell id="c" value="c" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="120" y="80" width="36" height="36" as="geometry"/>
    </mxCell>
    <mxCell id="d" value="d" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="280" y="80" width="36" height="36" as="geometry"/>
    </mxCell>
    <!-- Level 2 -->
    <mxCell id="ca" value="a" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="80" y="150" width="36" height="36" as="geometry"/>
    </mxCell>
    <mxCell id="co" value="o" style="ellipse;whiteSpace=wrap;html=1;fillColor=#DAE8FC;strokeColor=#6C8EBF;fontSize=14;fontFamily=Consolas;" vertex="1" parent="1">
      <mxGeometry x="160" y="150" width="36" height="36" as="geometry"/>
    </mxCell>
    <!-- Level 3 — word end nodes highlighted -->
    <mxCell id="cat" value="t" style="ellipse;whiteSpace=wrap;html=1;fillColor=#D5E8D4;strokeColor=#82B366;fontSize=14;fontFamily=Consolas;fontStyle=1;" vertex="1" parent="1">
      <mxGeometry x="80" y="220" width="36" height="36" as="geometry"/>
    </mxCell>
    <!-- "cat" label -->
    <mxCell id="catLabel" value="&quot;cat&quot;" style="text;html=1;fillColor=none;strokeColor=none;fontColor=#82B366;fontSize=10;align=center;" vertex="1" parent="1">
      <mxGeometry x="68" y="258" width="60" height="16" as="geometry"/>
    </mxCell>
    <!-- Edges -->
    <mxCell id="erc" style="strokeColor=#666;strokeWidth=1;endArrow=none;" edge="1" source="root" target="c" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="erd" style="strokeColor=#666;strokeWidth=1;endArrow=none;" edge="1" source="root" target="d" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="eca" style="strokeColor=#666;strokeWidth=1;endArrow=none;" edge="1" source="c" target="ca" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="eco" style="strokeColor=#666;strokeWidth=1;endArrow=none;" edge="1" source="c" target="co" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
    <mxCell id="ecat" style="strokeColor=#666;strokeWidth=1;endArrow=none;" edge="1" source="ca" target="cat" parent="1">
      <mxGeometry relative="1" as="geometry"/>
    </mxCell>
  </root>
</mxGraphModel>

Green nodes (#D5E8D4) mark word endings (isEnd=true).

Layout Tips

  1. Consistent spacing — Use 8px grid; tree levels at 80-100px vertical intervals
  2. Color meaning — Pick a legend and stick to it (blue=default, green=active, red=removed, yellow=visited)
  3. Monospace font — Always fontFamily=Consolas; for data values
  4. Index labels — Use small italic gray text above/below cells
  5. Pointer arrows — strokeWidth=2;endArrow=block;endFill=1; for linked structures
  6. Animation frames — Use draw.io pages for step-by-step algorithm visualization (page 1: initial, page 2: step 1, etc.)
  7. Null sentinels — Gray fill, dashed stroke, null or ∅ text