我修改的合并排序实现有什么问题？

Question

我试图将修改后的合并排序编写为练习。但我被困在为什么我的代码不工作，我不知道问题在哪里？！任何暗示或帮助都是值得欣赏的。提前谢谢。

这是我的代码：

public class MergeSort {

    public static void mergeSort(int[] list) {
        mergeSort(list, 0, list.length - 1);
    }

    private static void mergeSort(int[] list, int low, int high) {

        if (low < high) {

            int middle = (high + low) / 2;

            mergeSort(list, low, middle);

            mergeSort(list, middle + 1, high);

            int[] temp = merge(list, low, high);
            System.arraycopy(temp, 0, list, low, high - low + 1);
        }
    }

    private static int[] merge(int[] list, int low, int high) {

        int low1 = low;
        int high1 = high;
        int mid = (low + high) / 2;
        int end_low = mid;
        int start_high = mid + 1;

        while ((low <= end_low) && (start_high <= high1)) {
            if (list[low] < list[start_high]) {
                low++;
            } else {
                int temp = list[high - low + 1];
                for (int k = start_high - 1; k >= low; k--) {
                    list[k + 1] = list[k];
                }
                list[low] = temp;
                low++;
                end_low++;
                start_high++;
            }
        }

        return list;
    }

    public static void main(String[] args) {
        int[] list = { 2, 3, 2, 5, 6, 1, -2, 3, 14, 12, -5 };
        mergeSort(list);
        for (int i = 0; i < list.length; i++)
            System.out.print(list[i] + " ");
    }
}