希尔排序

图示

   

参考代码

void shellSort(int A[], int lens)

{

    if (A == NULL || lens <=0)

        return;

    for (int gap = lens/2; gap >0; gap /= 2)

    {

        for (int i = gap; i < lens; i+=1)

        {

            for (int j = i-gap; j >= 0 && A[j] > A[j+gap]; j-=gap)

                swap(A[j], A[j+gap]);

        }

    }

}

测试

#include <iostream>

using namespace std;



void shellSort(int A[], int lens)

{

    if (A == NULL || lens <=0)

        return;

    for (int gap = lens/2; gap >0; gap /= 2)

    {

        for (int i = gap; i < lens; i+=1)

        {

            for (int j = i-gap; j >= 0 && A[j] > A[j+gap]; j-=gap)

                swap(A[j], A[j+gap]);

        }

    }

}



void tranverse(int A[], int lens)

{

    for (int i = 0; i < lens; ++i)

        cout << A[i] << " ";

    cout << endl;

}



int main()

{

    int A[] = {5, 2, 9, 1, 3, 2, 2, 7};

    int lens = sizeof(A) / sizeof(*A);

    tranverse(A, lens);

    shellSort(A, lens);

    tranverse(A, lens);

}

View Code

性能

空间复杂度：O(1)

时间复杂度好于O(n²)

稳定性

不稳定