这有点复杂，没有 Java 标准 API 就无法完成。因此，我回收了一个快速排序实现并使其适用于多个数组。基本上，当元素被快速排序的分区交换时，它会交换元素。
干得好：
/**
* Multi-sorts the given arrays with the quicksort algorithm. It assumes that
* all arrays have the same sizes and it sorts on the first dimension of these
* arrays. If the given arrays are null or empty, it will do nothing, if just
* a single array was passed it will sort it via {@link Arrays} sort;
*/
public static void multiQuickSort(int[]... arrays) {
multiQuickSort(0, arrays);
}
/**
* Multi-sorts the given arrays with the quicksort algorithm. It assumes that
* all arrays have the same sizes and it sorts on the given dimension index
* (starts with 0) of these arrays. If the given arrays are null or empty, it
* will do nothing, if just a single array was passed it will sort it via
* {@link Arrays} sort;
*/
public static void multiQuickSort(int sortDimension, int[]... arrays) {
// check if the lengths are equal, break if everything is empty
if (arrays == null || arrays.length == 0) {
return;
}
// if the array only has a single dimension, sort it and return
if (arrays.length == 1) {
Arrays.sort(arrays[0]);
return;
}
// also return if the sort dimension is not in our array range
if (sortDimension < 0 || sortDimension >= arrays.length) {
return;
}
// check sizes
int firstArrayLength = arrays[0].length;
for (int i = 1; i < arrays.length; i++) {
if (arrays[i] == null || firstArrayLength != arrays[i].length)
return;
}
multiQuickSort(arrays, 0, firstArrayLength, sortDimension);
}
/**
* Internal multi quicksort, doing the real algorithm.
*/
private static void multiQuickSort(int[][] a, int offset, int length,
int indexToSort) {
if (offset < length) {
int pivot = multiPartition(a, offset, length, indexToSort);
multiQuickSort(a, offset, pivot, indexToSort);
multiQuickSort(a, pivot + 1, length, indexToSort);
}
}
/**
* Partitions the given array in-place and uses the end element as pivot,
* everything less than the pivot will be placed left and everything greater
* will be placed right of the pivot. It returns the index of the pivot
* element after partitioning. This is a multi way partitioning algorithm, you
* have to provide a partition array index to know which is the array that
* needs to be partitioned. The swap operations are applied on the other
* elements as well.
*/
private static int multiPartition(int[][] array, int start, int end,
int partitionArrayIndex) {
final int ending = end - 1;
final int x = array[partitionArrayIndex][ending];
int i = start - 1;
for (int j = start; j < ending; j++) {
if (array[partitionArrayIndex][j] <= x) {
i++;
for (int arrayIndex = 0; arrayIndex < array.length; arrayIndex++) {
swap(array[arrayIndex], i, j);
}
}
}
i++;
for (int arrayIndex = 0; arrayIndex < array.length; arrayIndex++) {
swap(array[arrayIndex], i, ending);
}
return i;
}
/**
* Swaps the given indices x with y in the array.
*/
public static void swap(int[] array, int x, int y) {
int tmpIndex = array[x];
array[x] = array[y];
array[y] = tmpIndex;
}
做了一个小测试用例来测试你对问题的输入：
@Test
public void testMultiQuickSort() {
int[] first = new int[] { 10, 100, 100, 0 };
int[] second = new int[] { 1, 3, 2, 4 };
int[] resFirst = new int[] { 0, 10, 100, 100 };
int[] resSecond = new int[] { 4, 1, 2, 3 };
ArrayUtils.multiQuickSort(first, second);
for (int i = 0; i < first.length; i++) {
assertEquals(resFirst[i], first[i]);
assertEquals(resSecond[i], second[i]);
}
}
似乎工作;）
顺便说一句，如果您需要它用于任意对象类型，请发表评论。