public class FaskSort {
    private static int count0 = 0;
    public  static void sort(int[] array){
        if(array.length > 0){
            sort(array, 0, array.length - 1);
        }
    }

    private static void sort(int[] array, int low, int high){
        count0++;
        int p_pos = low;// 分界索引
        int p_voint = array[low];// 基值
        int temp;
        for (int i = low + 1; i <= high; i++){
            if(array[i] < p_voint){
                p_pos++;
                if(p_pos != i){// 索引相同避免交換
                    temp = array[p_pos];
                    array[p_pos] = array[i];
                    array[i] = temp;
                }
            }
        }
        // 把基準值放到排好序的最後位置
        if(p_pos != low){
            temp = array[p_pos];
            array[p_pos] = array[low];
            array[low] = temp;
        }
        if(p_pos - 1 > low){
            sort(array, low, p_pos - 1);
        }
        if(high > p_pos + 1){
            sort(array, p_pos + 1, high);
        }
    }

    private static int count1 = 0;

    public static void sort1(int[] array){
        if(array.length > 0){
            sort1(array, 0, array.length - 1);
        }
    }
    private static void sort1(int[] array, int low, int high){
        count1++;
        int i = low +1;
        int j = high;
        int key = array[low];
        int temp;
        while (i < j){
            while(i < j && array[i] < key){// i < j時從左往右找大於key的 索引
                i++;
            }
            while(i < j && array[j] > key ){// i < j時從右往左找小於key的 索引
                j--;
            }
            if(i < j){// 然後交換
                temp = array[j];
                array[j] = array[i];
                array[i] = temp;
            }
        }
        if (array[i] >= key) {// 由於上面while退出條件的缺陷 進行修正，此時i索引處左邊全是小於key
            i--;
        }
        temp = array[i];
        array[i] = array[low];
        array[low] = temp;
        if(i -1 > low){
            sort1(array, low, i -1);
        }
        if(high > i + 1){
            sort1(array, i + 1, high);
        }
    }

    public static void main(String[] args) {
        {
            int[] array = {6, 4, 7, 5, 9, 3, 2, 1, 8};
            sort(array);
            System.out.println(Arrays.toString(array));
            System.out.println(count0);
        }
        {
            int[] array1 = {6, 4, 7, 5, 9, 3, 2, 1, 8};
            sort1(array1);
            System.out.println(Arrays.toString(array1));
            System.out.println(count1);
        }
    }
}