希爾排序

對於一個int數組，請編寫一個希爾排序算法，對數組元素排序。
給定一個int數組A及數組的大小n，請返回排序後的數組。保證元素小於等於2000。

測試樣例：

[1,2,3,5,2,3],6
[1,2,2,3,3,5]
個人提交

-- coding:utf-8 --

class ShellSort:
def shellSort(self, A, n):

write code here

step_num = 1
    if n > 5:
        step_num = n // 2

    while step_num >= 1:
        for i in range(step_num, n):
            t = A[i]
            j = i
            while j >= step_num and t < A[j-step_num]:
                A[j] = A[j-step_num]
                j -= step_num

            A[j] = t
        step_num = step_num // 2
        # print("step_num = " + str(step_num) + " -> " + str(A))
    return A

if name == 'main':
shell = ShellSort()
print(shell.shellSort([54,35,48,36,27,12,44,44,8,14,26,17,28],13))
參考答案
public class ShellSort {

public static void shellSort(int[] arr) {
    if (arr == null || arr.length < 2) {
        return;
    }
    int feet = arr.length / 2;
    int index = 0;
    while (feet > 0) {
        for (int i = feet; i < arr.length; i++) {
            index = i;
            while (index >= feet) {
                if (arr[index - feet] > arr[index]) {
                    swap(arr, index - feet, index);
                    index -= feet;
                } else {
                    break;
                }
            }
        }
        feet /= 2;
    }
}

public static void swap(int[] arr, int index1, int index2) {
    int tmp = arr[index1];
    arr[index1] = arr[index2];
    arr[index2] = tmp;
}

public static int[] generateArray(int len, int range) {
    if (len < 1) {
        return null;
    }
    int[] arr = new int[len];
    for (int i = 0; i < len; i++) {
        arr[i] = (int) (Math.random() * range);
    }
    return arr;
}

public static void printArray(int[] arr) {
    if (arr == null || arr.length == 0) {
        return;
    }
    for (int i = 0; i < arr.length; i++) {
        System.out.print(arr[i] + " ");
    }
    System.out.println();
}

public static boolean isSorted(int[] arr) {
    if (arr == null || arr.length < 2) {
        return true;
    }
    for (int i = 1; i < arr.length; i++) {
        if (arr[i - 1] > arr[i]) {
            return false;
        }
    }
    return true;
}

public static void main(String[] args) {
    int len = 10;
    int range = 10;
    int testTimes = 50000;
    for (int i = 0; i < testTimes; i++) {
        int[] arr = generateArray(len, range);
        shellSort(arr);
        if (!isSorted(arr)) {
            System.out.println("Wrong Case:");
            printArray(arr);
            break;
        }
    }

    int len2 = 13;
    int range2 = 10;
    int testTimes2 = 50000;
    for (int i = 0; i < testTimes2; i++) {
        int[] arr = generateArray(len2, range2);
        shellSort(arr);
        if (!isSorted(arr)) {
            System.out.println("Wrong Case:");
            printArray(arr);
            break;
        }
    }
}

}