排序篇:quick

快速排序quickSort

public class Test {
    public static void main(String[] args) {
        int arr[] = {3, 5, 6, 333, 5, 2, 1111, 1, 2, 3, 4, 5, 6, 7, 8, 8};
        quickSort(arr, 0, arr.length - 1);
    }
    public static void quickSort(int arr[], int start, int end) {
        if (start >= end) {return;}
        int prviod = partion(arr, start, end);
        quickSort(arr, start, prviod - 1);
        quickSort(arr, prviod + 1, end);
    }
    public static int partion(int arr[], int start, int end) {
        int j = start - 1;
        int index = start;
        for (; index < end; index++) {
            if (arr[index] < arr[end]) {
                swap(arr, j + 1, index);
                j++;
            }
        }
        swap(arr, j + 1, end);
        System.out.println(Arrays.toString(arr));
        return j + 1;
    }
    public static void swap(int arr[], int j, int index) {
        int tmp = arr[j];
        arr[j] = arr[index];
        arr[index] = tmp;
    }
}