2026 Term 1 · Afternoon — Worked Solutions
Every question solved from scratch: the reasoning, the algorithm trace, and the shortcuts that get you to the answer fast.
Q1 — Search: Water Jug BFS
Three move types on the 5-3-2 jug set: BFS level-counting finds 212 to 131 in three pours and proves nothing shorter exists.
Q2 — Search Algorithms Theory
Three guarantee questions: DFID's closed-list secret, which algorithms survive an unknown heuristic, and why wA* at infinity forgets g entirely.
Q3 — Games: Alpha-Beta Pruning Puzzle
Design the leaf values yourself: with window (1,3) the best you can do is kill B and D, and four assignments achieve it.
Q4 — Games: SSS* Algorithm
Ten leaves, three subtrees: SSS* crowns seven leaves SOLVED, and the four first-born witnesses get purged the moment their MAX ancestors fall.
Q4 — AO* Problem Decomposition
Edge cost 2, shared primitive H feeding three parents, and a marker that tours C-A-B-F before every keyed value clicks into place.
Q5 — Rule Based Expert Systems
Nine mushroom WMEs, four joins, four surviving tuples - and one fresh timestamp (107) hands recency straight to R1.
Q7 — Automated Planning Theory
GraphPlan's fine print: when two orderings are twins, exactly which precondition/effect overlaps make actions mutex, and the monotonicity of NON-mutex.
Q8 — Automated Planning: GraphPlan
FSSP forward, BSSP backward, then a full GraphPlan run: three actions fire, two writers matter, and the 5-step plan pops out of the mutual-exclusion maze.
Q8 — Constraint Satisfaction: AC and PC
Three mod-relations over {1..4}: compute the tables, watch arc-consistency shave value 3 off every domain, then hunt the unique solution 2,4,1.