Daily Writeups

Browse all daily problem writeups, organized chronologically. Each writeup includes the problem approach, AP CSA compliance notes, and learning objectives addressed.

Day 1: Secret Entrance


AP-CSA LO-1.3.C LO-1.15.B LO-2.3.A LO-2.5.A LO-2.7.B LO-4.7.A LO-4.8.A LO-4.9.A modulo iteration arithmetic string-methods

Day 2: Gift Shop


AP-CSA LO-1.3.C LO-1.15.B LO-2.3.A LO-2.7.B LO-2.8.A LO-4.3.A LO-4.9.A string-manipulation patterns long-exception

Day 3: Lobby


AP-CSA LO-1.3.C LO-1.15.B LO-2.3.A LO-2.7.B LO-2.8.A LO-4.1.A LO-4.2.A LO-4.9.A greedy-algorithm arrays string-manipulation subsequences

Day 4: Printing Department


AP-CSA LO-1.3.C LO-2.3.A LO-2.7.B LO-2.8.A LO-4.1.A LO-4.2.A LO-4.9.A 2D-arrays simulation cellular-automaton debugging

Day 5: Cafeteria


AP-CSA CSTA LO-1.3.C LO-2.3.A LO-2.7.B LO-2.8.A LO-4.1.A LO-4.8.A LO-4.9.A ranges interval-merging YAGNI debugging problem-solving

Day 6: Trash Compactor


AP-CSA CSTA MOD-1.C MOD-1.E CON-2.A.1 CON-2.B VAR-2.E.1 VAR-2.E.2 VAR-2.F Scanner 2D-arrays identity-values parsing nested-loops

Day 7: Tachyon Beam Splitters


AP-CSA CSTA beyond-subset recursion memoization dynamic-programming performance-optimization CON-2.B VAR-2.E MOD-3.B HashSet HashMap call-stack

Day 9: Largest Rectangle


AP-CSA LO-1.3.C LO-2.3.A LO-2.5.A LO-4.7.A LO-4.8.A LO-4.9.A run-length-encoding ray-casting even-odd-rule polygon-filling sorting-optimization pre-filling row-wise-verification

Day 10: Factory


AP-CSA CSTA CSTA-1A-AP-11 CSTA-2-AP-13 CSTA-2-AP-14 beyond-subset BFS recursion memoization state management optimization VAR-1.A MOD-2.A CON-2.A VAR-2.E VAR-2.F AAP-1.A

Day 12: Christmas Tree Farm


AP-CSA CSTA CSTA-2-AP-10 CSTA-2-AP-13 CSTA-2-AP-14 beyond-subset backtracking heuristics optimization VAR-1.A MOD-2.A CON-2.A VAR-2.E VAR-2.F AAP-1.A