import java.util.Arrays;

public class Main {

    public static void main(String[] args) {

        int[] a = { 6, -2, 7, 8, 3, 4, 12, 1, 0, -3, -8, 3, 4, 7 };

        System.out.println("排序之前：" + Arrays.toString(a));

        sort(a, 0, a.length - 1);

        System.out.println("排序之后：" + Arrays.toString(a));

    }

    public static int[] sort(int[] a, int low, int high) {

        int mid = (low + high) / 2;

        if (low < high) {

            sort(a, low, mid);

            sort(a, mid + 1, high);

            merge(a, low, mid, high);

        }

        return a;

    }

    public static void merge(int[] a, int low, int mid, int high) {

        int[] temp = new int[high - low + 1];

        int i = low;

        int j = mid + 1;

        int k = 0;

        // 将两数组中较小的放入temp

        while (i <= mid && j <= high) {

            if (a[i] < a[j]) {

                temp[k] = a[i];

                k++;

                i++;

            } else {

                temp[k] = a[j];

                k++;

                j++;

            }

        }

        // 将剩余的放入temp

        while (i <= mid) {

            temp[k] = a[i];

            k++;

            i++;

        }

        while (j <= high) {

            temp[k] = a[j];

            k++;

            j++;

        }

        // 用temp覆盖a

        for (int k2 = 0; k2 < temp.length; k2++) {

            a[k2 + low] = temp[k2];

        }

    }

}