{"id":"min-of-adjacent-groups","text":"In `count_binary_substrings`, the number of valid binary substrings spanning two adjacent groups of sizes a and b is exactly `min(a, b)` — this is the mathematical invariant the O(1)-space algorithm relies on.","truth_value":"IN","source":"entries/2026/06/06/count-binary-substrings-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"min-of-adjacent-groups","truth_value":"IN","reason":"premise"}]}}