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Multi-Goal A*

Multi-Goal A* addresses multi-target pathfinding by searching toward the best among several goals using admissible goal estimates.

Quick Facts

Compact metadata for implementation and discovery.

Category
Pathfinding
Difficulty
Intermediate
Family
Heuristic Search
Tier
Extended
Status
Verified
Review
Source Checked
Sources
1
Formulas
0
Relationships
1
Code example
Ready
Visualization
Ready

Overview

Multi-Goal A* is a heuristic search method for multi-target pathfinding. It works by searching toward the best among several goals using admissible goal estimates.

Core Concepts

multi-target pathfindingheuristic searchpathfinding

Quick facts

Complexity

Runtime and memory behavior at a glance.

Best

O(1)

Average

O(n)

Worst

O(n)

Space

O(1)

When to Use

  • Use Multi-Goal A* when solving multi-target pathfinding and you want to benefit from searching toward the best among several goals using admissible goal estimates.
  • Choose it when O(n) average/worst-case time and O(1) memory match your workload profile.
  • Prefer it over Visibility Graph Roadmap or 0-1 BFS when the problem structure favors multi-target pathfinding.

When Not to Use

  • Avoid when path costs or obstacles change in ways the method cannot update efficiently.
  • Avoid when approximate paths are unacceptable and the method does not guarantee optimality.

What It Does

  • Computes multi-target pathfinding within Heuristic Search workloads (O(n) time, O(1) space).
  • Works by searching toward the best among several goals using admissible goal estimates.
  • Maintains key invariants across multi-target pathfinding, heuristic search, pathfinding.

Use Cases

  • Production and research workloads requiring multi-target pathfinding via searching toward the best among several goals using admissible goal estimates.
  • Heuristic Search pipelines where O(n) time and O(1) space fit system constraints.
  • Engineering comparisons against Visibility Graph Roadmap and 0-1 BFS when tuning multi-target pathfinding.

Inputs

  • Heuristic Search input instance for multi-target pathfinding
  • Configuration parameters controlling multi-target pathfinding

Outputs

  • Computed multi-target pathfinding solution produced by Multi-Goal A*
  • Diagnostic state over multi-target pathfinding and heuristic search

Pseudocode

  1. 1.Initialize the search space, start/goal states, and cost/priority tables for Multi-Goal A*.
  2. 2.Insert the initial state into the open frontier or roadmap with its baseline cost and heuristic estimate.
  3. 3.Expand or sample candidate transitions by searching toward the best among several goals using admissible goal estimates.
  4. 4.Update path costs, parent pointers, or conflict constraints whenever an improved trajectory is found.
  5. 5.Reconstruct and return the collision-free path from start to goal once the termination criterion holds.

Canonical Example

Input
Heuristic Search input instance for multi-target pathfinding configured for a representative multi-target pathfinding test case
Output
Computed multi-target pathfinding solution produced by Multi-Goal A* satisfying Multi-Goal A* invariants
Explanation
Multi-Goal A* processes the input by searching toward the best among several goals using admissible goal estimates, tracking multi-target pathfinding and heuristic search to produce the verified multi-target pathfinding result.

Implementation Notes

  • Separate search state from world state so changes can be tested.
  • Use small maps with known optimal answers before large scenarios.
  • Track whether returned paths are optimal, bounded, or heuristic.

Common Pitfalls

  • Using an inadmissible heuristic where optimality is expected.
  • Ignoring dynamic obstacles, time-dependent costs, or changing edge weights.
  • Testing only open grids and missing narrow-passage cases.

Interactive Mechanism Walkthrough

2D Grid Wavefront & Trajectory

Show searching toward the best among several goals using admissible goal estimates on a small multi-target pathfinding example.

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Step 1 of 5: Initialize the search space, start/goal states, and cost/priority tables for Multi-Goal A*.
pathfinding-mechanism

Notes

Multi-Goal A* operates in O(n) time and O(1) space within the Heuristic Search family. Often compared with Visibility Graph Roadmap and 0-1 BFS.

Sources (1)

What each reference supports for this entry.

Artificial Intelligence: A Modern Approach

Book

AI search reference supporting Multi-Goal A* heuristic evaluation, frontier ordering, replanning behavior, or completeness tradeoffs.

Open source

Explore Next

Good next jumps from the relationship graph, ranked for useful discovery.

Conceptual neighborGreedy Best-First Search

Both use heuristic priorities to guide search, while Multi-Goal A* evaluates termination against multiple targets.

Tags

PathfindingGraph