stable vs. unstable sorts
Definition Stable and unstable is depend on how sort any duplicated list. If the algorithm keeps original position of duplicated values, it is stable sort algorithm If the algorithm positioned duplicated values randomly, it is unstable sort algorithm Example raw list=[3(1), 7(1), 3(2), 4, 7(2), 9] stable sorted list=[3(1), 3(2), 4, 7(1), 7(2), 9] unstable sorted list=[3(2), 3(1), 4, 7(2), 7(1), 9] Stable Sorting Bubble Sort Insertion Sort Merge Sort