03-24 [LeetCode][881. Boats to Save People] Greedy: Let the Heaviest Match the Lightest, if Not Matched, Let it Alone
02-18 [LeetCode][287. Find the Duplicate Number] 9 Approaches：Brute Force, Count, Hash, In-place Marked, Sorting, Index Sort, Binary Search, Bit Manipulation, Fast Slow Pointers