Java排序七：快排

public class TestDemo {
public static void main(String[] args) {
int[] arr = new int[10];
Random random = new Random();
for (int i = 0; i < arr.length; i++) {
arr[i] = random.nextInt(100);
}
display(arr);
sort(arr, 0, arr.length - 1);
display(arr);
}

public static void sort(int[] arr, int left, int right) {
if (left < right) {
int partition = getPartition(arr, left, right);
sort(arr, left, partition - 1);
sort(arr, partition + 1, right);
}
}

private static int getPartition(int[] arr, int left, int right) {
int temp = arr[left];
while (left < right) {
while (arr[right] >= temp && left < right) {
right--;
}
if (left < right) {
arr[left++] = arr[right];
}
while (arr[left] <= temp && left < right) {
left++;
}
if (left < right) {
arr[right--] = arr[left];
}
}
arr[left] = temp;
return left;
}

private static void swap(int[] arr, int i, int j) {
if (i == j) {
return;
}
arr[i] = arr[i] ^ arr[j];
arr[j] = arr[i] ^ arr[j];
arr[i] = arr[i] ^ arr[j];
}

private static void display(int[] arr) {
for (int i = 0, len = arr.length; i < len; i++) {
System.out.print(arr[i] + "  ");
}
System.out.println();
}
}