Dijkstra’s vs A* Pathfinding Algorithms

🔹 Dijkstra’s Algorithm

What it does: Finds the shortest path from a start node to all other nodes in a graph.
Heuristic: ❌ None (it doesn’t “guess” distance, just explores all possible paths).
Performance: Can be slow on large graphs, since it explores many unnecessary nodes.
Guarantee: Always finds the shortest path.
Use cases:
- Network routing
- GPS when no heuristic is available
- General shortest-path problems

🔹 A Algorithm*

What it does: Finds the shortest path from a start node to a target node efficiently.
Heuristic: ✅ Uses a heuristic function f(n) = g(n) + h(n)
- g(n) = cost so far
- h(n) = estimated cost to goal (heuristic)
Performance: Much faster, explores fewer nodes than Dijkstra (if heuristic is good).
Guarantee: Finds the shortest path if the heuristic is admissible (never overestimates).
Use cases:

- Pathfinding in games (NPC navigation, maps)
- Robotics movement
- GPS navigation with heuristics (like straight-line distance)

#datastructures #datastructureandalgorithm