示例：实现合并排序算法的Java程序
import java.util.Arrays;
// Merge sort in Java
class Main {
// Merge two sub arrays L and M into array
void merge(int array[], int p, int q, int r) {
int n1 = q - p + 1;
int n2 = r - q;
int L[] = new int[n1];
int M[] = new int[n2];
// fill the left and right array
for (int i = 0; i < n1; i++)
L[i] = array[p + i];
for (int j = 0; j < n2; j++)
M[j] = array[q + 1 + j];
// Maintain current index of sub-arrays and main array
int i, j, k;
i = 0;
j = 0;
k = p;
// Until we reach either end of either L or M, pick larger among
// elements L and M and place them in the correct position at A[p..r]
// for sorting in descending
// use if(L[i] >= 输出1
Unsorted Array:
[6, 5, 12, 10, 9, 1]
Sorted Array:
[1, 5, 6, 9, 10, 12]在此，数组的元素按升序排序。如果要按降序对元素进行排序，则可以在merge()方法的第一个while循环内， merge()代码更改为：
// the less than sign is changed to greater than
if (L[i] >= M[j]) {如果您想了解有关合并排序算法的更多信息，请访问合并排序算法。