三种插入排序

#include<iostream>
using namespace std;
//直接插入排序
void InsertSort(int a[], int n)
{
    int i, j, key;
    for (i = 1; i < n; i++)
    {
        key = a[i];
        j = i-1;
        while (j >= 0 && a[j]>key)
        {
            a[j + 1] = a[j];
            j--;
        }
        a[j + 1] = key;

    }
}
//希尔插入排序
void shellsort(int a[], int n)
{
    int k, i, gap;

    for (gap = n / 2; gap > 0; gap /= 2) //步长
    {
        for (k = 0; k < gap; k++)        //直接插入排序
        {
            for (i = k + gap; i < n; i += gap)
                //if (a[j] < a[j - gap])
            {
                int key = a[i];
                int j = i - gap;
                while (j >= 0 && a[j] > key)
                {
                    a[j + gap] = a[j];
                    j -= gap;
                }
                a[j + gap] = key;
            }
        }
    }
}
//二分插入
void binsert(int a[], int n)
{
    int key, left, right;
    for (int i = 1; i < n; i++)
    {
        left = 0;
        right = i - 1;
        key = a[i];
        while (left <= right)
        {
            int middle = (left + right) / 2;//最好写成 right+(right-left)/2;
            if (a[middle]>key)
                right = middle - 1;
            else
                left = middle + 1;
        }
        for (int j = i - 1; j >= left; j--)
        {
            a[j + 1] = a[j];
        }
        a[left] = key;

    }
}

int main()
{
    int a[10];
    for (int i = 0; i < 10; i++)
        cin >> a[i];
    for (auto t : a)
        cout << t << " ";
    cout << endl;
    InsertSort(a, 10);// 直接插入排序
    for (auto t : a)
        cout << t << " ";
    cout << endl;
    shellsort(a, 10); //希尔排序
    for (auto t : a)
        cout << t << " ";
    cout << endl;
    binsert(a, 10);  // 二分插入
    for (auto t : a)
        cout << t << " ";
    cout << endl;
    system("pause");
    return 0;
}