AI · Theory

Greedy Best-First Search

Theory

85/215

Greedy Best-First Search

Greedy best-first expands the node that looks closest to the goal (smallest h only). Fast, not guaranteed optimal. Can walk into a dead alley. A* adds g so you don’t ignore cost already paid.

Greedy Best-First Search — output — three exam lines. Graph on paper first.

Diagram

start
    ├── BFS  queue
    ├── DFS  stack
    └── A*   g+h
    │
    ▼
   goal

Exam tip

Greedy vs A*: h vs g+h.

Example

# Greedy Best-First Search
print("draw 6 nodes")
print("name the DS: queue / stack / priority")
print("say if the path is optimal")

Greedy Best-First Search — output: three exam lines. Graph on paper first.

Short notes

DefUses only h(n). Not always optimal.

AI · Theory

Greedy Best-First Search

← All stacks

Theory

85/215

Greedy Best-First Search

Greedy best-first expands the node that looks closest to the goal (smallest h only). Fast, not guaranteed optimal. Can walk into a dead alley. A* adds g so you don’t ignore cost already paid.

Greedy Best-First Search — output — three exam lines. Graph on paper first.

Diagram

start
    ├── BFS  queue
    ├── DFS  stack
    └── A*   g+h
    │
    ▼
   goal

Exam tip

Greedy vs A*: h vs g+h.

Example

# Greedy Best-First Search
print("draw 6 nodes")
print("name the DS: queue / stack / priority")
print("say if the path is optimal")

Greedy Best-First Search — output: three exam lines. Graph on paper first.

Short notes

DefUses only h(n). Not always optimal.

Greedy Best-First Search

Example

Short notes

Questions

Greedy Best-First Search

Example

Short notes

Questions