合并排序算法java实现

好的，合并排序算法的Java实现如下：

public class MergeSort {
    public static void mergeSort(int[] arr, int left, int right) {
        if (left < right) {
            int mid = (left + right) / 2;
            mergeSort(arr, left, mid);
            mergeSort(arr, mid + 1, right);
            merge(arr, left, mid, right);
        }
    }

    private static void merge(int[] arr, int left, int mid, int right) {
        int[] tempArr = new int[right - left + 1];
        int i = left, j = mid + 1, curr = 0;
        while (i <= mid && j <= right) {
            if (arr[i] < arr[j]) {
                tempArr[curr++] = arr[i++];
            } else {
                tempArr[curr++] = arr[j++];
            }
        }
        while (i <= mid) {
            tempArr[curr++] = arr[i++];
        }
        while (j <= right) {
            tempArr[curr++] = arr[j++];
        }
        for (int k = 0; k < tempArr.length; k++) {
            arr[left + k] = tempArr[k];
        }
    }
}

该算法的时间复杂度为O(nlogn)，可以对任意长度的数组进行排序。