How to Solve Mazes: From Right-Hand Rule to A* (With Visuals)

2025-10-10โ€ข12 min readโ€ขBy Qin WenLong
StrategyGuideBFSDijkstraA*

How to Solve Mazes: From Right-Hand Rule to A* (With Visuals)

Want to solve mazes systematically? This guide covers intuitive and algorithmic approaches, explains when each works best, and offers speedrun tips.

1) Right-Hand Rule (Wall Following)

  • Intuition: keep your right hand on the wall and keep moving
  • Best for: simple, connected planar mazes; does not guarantee shortest path
  • Limitation: can loop in mazes with cycles

Practice

  • Try it in /maze; zoom in slightly and focus on consistent wall contact

2) Junction Mapping

  • Mark each junction (on paper or mentally) to avoid revisiting explored branches
  • Ideal for medium-complexity mazes

3) BFS (Breadth-First Search)

  • Guarantees the shortest path (if edges are unweighted)
  • Works well for grid mazes; time O(V+E)

Pseudocode

```text queue = [start] visited = {start: null} while queue not empty: cur = queue.pop_front() if cur == goal: break for each neighbor in neighbors(cur): if neighbor not in visited: visited[neighbor] = cur queue.push_back(neighbor)

path = reconstruct from visited[goal]
```

4) Dijkstra (equivalent to BFS when edges are equal)

  • Use for weighted terrains (different movement costs)
  • Priority queue recommended; complexity O(E log V)

5) A* (Heuristic Search)

  • f(n)=g(n)+h(n); use Manhattan distance for grid mazes
  • Reduces expansions and speeds up search under similar heuristics

Speedrun Tips

  • Route review: after finishing, revisit key junctions to find potential shortcuts
  • Visualization: keep an active mental boundary of unexplored regions
  • Rhythm: avoid excessive backtracking; prioritize frontier expansion

Common Pitfalls

  • Overusing wall-following in complex mazes
  • Failing to mark junctions, leading to repeated exploration

Practice & Tools

FAQ

Is A* always faster than BFS? Not necessarily. BFS can be very fast on certain structures; A* shines by expanding fewer nodes.

How to practice on mobile?
Use touch swipe controls; start with low complexity and ramp up gradually.

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