代码

public static void quickSort(int[] arr, int start, int end) {
        //start和end以下标0开始为基准
        if (start < end) {
            int k = partition(arr, start, end);
            quickSort(arr, start, k-1);
            quickSort(arr, k+1, end);
        }
    }

    public static int partition(int[] arr, int start, int end) {
        int temp = arr[start];//存起来
        while(start < end) {
            while(start < end && arr[end] >= temp) end--;
            arr[start] = arr[end];
            while(start < end && arr[start] <= temp) start++;
            arr[end] = arr[start];
        }
        arr[start] = temp;
        return start;
    }