{"id":"additive-then-subtractive-counting-pattern","text":"Grid geometry problems (surface area, island perimeter) use an \"add full contribution, then subtract shared faces\" strategy — computing isolated values first, then removing occlusion — as a reusable template.","truth_value":"IN","source":"entries/2026/06/06/surface-area-of-3d-shapes-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"additive-then-subtractive-counting-pattern","truth_value":"IN","reason":"premise"}]}}