---
title: 'Decision-Space'
description: 'Nodes are states, not data. The structure does not exist until you walk it.'
sidebar:
  order: 1
  label: Introduction
---

:::warning[Under construction]
This page is a scaffold. Notes, canonical problems, and template code are not written yet.
:::

## Patterns

- [Backtracking](/guides/coding/decision-space/backtracking) — DFS over the state tree with undo; exhaustive enumeration.
- [Dynamic Programming](/guides/coding/decision-space/dynamic-programming) — Backtracking plus memoization over overlapping subproblems.
- [Greedy](/guides/coding/decision-space/greedy) — DP where the local optimum provably suffices, so no memo is needed.

**Systems anchor:** DP memo is an idempotency cache; backtracking is a saga with compensating undo; greedy is local decisions that converge.