🌳 Tree DP & Graph Editor

An interactive Graph Editor & Tree DP Visualizer for competitive programming — build trees visually, write DP formulas in a mini DSL, run them, and see results on every node.

🔗 Live: https://angelator312.github.io/tree-dp-and-graph-editor/

✨ Features

• Visual Graph Editor — Add, connect, edit, drag nodes on a canvas
• Tree DP Engine — Write formulas, run with Ctrl+Enter, see results instantly
• 30+ DSL Functions — sum, prod, min, max, abs, gcd, lcm, filter, map, prefix, suffix, and more
• Pre-built Examples — 9 classic tree DP problems ready to load (Subtree Size, Max Independent Set, Min Vertex Cover, Tree Diameter, Sum of Distances, Tree Matching, Tree Coloring, Longest Path)
• Custom Formulas — Save your own formulas to the dropdown for quick access
• All Tree DP Types — Subtree (bottom-up), Rerooting (top-down via par()), multi-state, edge-weighted
• CP Format Export — Copy tree data in competitive programming format
• Undo/Redo, Import/Export, localStorage persistence
• Example Files — All example formulas available in the examples/ folder

🚀 Quick Start

1. Open the live site
2. Click Add (A) mode and click on the canvas to add nodes
3. Switch to Connect (C) mode and click two nodes to create an edge
4. Pick an example from the Examples dropdown, or write your own formula
5. Click Run (Ctrl+Enter) to compute DP values
6. Check the Data tab for a table of all node values

📐 DSL Reference

Variables

Variable	Description
val	Node weight
children	Array of child IDs
edgeWeight	Edge weight to this node
id	Node ID
childCount	Number of children
isLeaf	1 if leaf, 0 otherwise
depth	Depth from root (root = 0)
subtreeSize	Subtree size including self
n	Total number of nodes

Functions

Aggregation: sum, prod, max, min, count, avg Math: abs, floor, ceil, sqrt, log, log2, pow, mod, gcd, lcm, sign, clamp Access: par(var), len(arr), allNodes(), findNodes(condition) Arrays: range, map, filter, sort (supports "asc"/"desc" as last arg), reverse, concat, unique, flatten, prefix, suffix, slice, indexOf

Operators

+ - * / % ^ == != < > <= >= && || ! ? :

📝 Example Formulas

# Subtree Size
sz = sum(children, sz) + 1

# Max Independent Set
dp0 = sum(children, max({dp0, dp1}))
dp1 = sum(children, dp0) + val

# Sum of Distances (Rerooting)
sz = sum(children, sz) + 1
down = sum(children, down + sz)
ans = par(ans) - sz + (n - sz) + down

# Count nodes matching condition
highWeightCount = len(findNodes(val > 5))
leafCount = len(findNodes(isLeaf == 1))

# get root weight using findNodes and map
rootWeight = map(findNodes(isRoot == 1), val)[0]

# Sort children by DP value descending
topChild = sort(children, dp, "desc")[0]

🛠️ Setup for GitHub Pages

1. Fork or clone this repo
2. Go to Settings → Pages → Source: main branch, / (root)
3. Your site is live!