From 813b790214bcaa9ce9d47bafe9003ada16abc310 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=D0=94=D1=8E=D1=80=D1=8F=D0=B3=D0=B8=D0=BD=20=D0=94=D0=B0?= =?UTF-8?q?=D0=BD=D0=B8=D0=BB?= Date: Sun, 23 Aug 2026 19:36:33 +0300 Subject: [PATCH] feat(sorting): implement merge sort strategy --- .../test/java/sorting/MergeSortStrategy.java | 65 +++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 app/src/test/java/sorting/MergeSortStrategy.java diff --git a/app/src/test/java/sorting/MergeSortStrategy.java b/app/src/test/java/sorting/MergeSortStrategy.java new file mode 100644 index 0000000..86655f7 --- /dev/null +++ b/app/src/test/java/sorting/MergeSortStrategy.java @@ -0,0 +1,65 @@ +package sorting; + +import java.util.Comparator; + +public class MergeSortStrategy implements SortStrategy { + + @Override + public void sort(MyList list, Comparator comparator) { + if (list == null || list.size() <= 1) { + return; + } + mergeSort(list, 0, list.size() - 1, comparator); + } + + private void mergeSort(MyList list, int left, int right, Comparator comparator) { + if (left >= right) { + return; + } + int mid = (left + right) / 2; + mergeSort(list, left, mid, comparator); + mergeSort(list, mid + 1, right, comparator); + merge(list, left, mid, right, comparator); + } + + private void merge(MyList list, int left, int mid, int right, Comparator comparator) { + int leftSize = mid - left + 1; + int rightSize = right - mid; + + @SuppressWarnings("unchecked") + T[] leftArray = (T[]) new Object[leftSize]; + @SuppressWarnings("unchecked") + T[] rightArray = (T[]) new Object[rightSize]; + + for (int i = 0; i < leftSize; i++) { + leftArray[i] = list.get(left + i); + } + for (int j = 0; j < rightSize; j++) { + rightArray[j] = list.get(mid + 1 + j); + } + + int i = 0, j = 0, k = left; + + while (i < leftSize && j < rightSize) { + if (comparator.compare(leftArray[i], rightArray[j]) <= 0) { + list.set(k, leftArray[i]); + i++; + } else { + list.set(k, rightArray[j]); + j++; + } + k++; + } + + while (i < leftSize) { + list.set(k, leftArray[i]); + i++; + k++; + } + while (j < rightSize) { + list.set(k, rightArray[j]); + j++; + k++; + } + } +} \ No newline at end of file