Sort - split half insertion sort

Binary insertion sort

When looking for an element using binary search to improve efficiency

#include <iostream>
using namespace std;
#define  MAXSIZE  20                    //顺序表的最大长度
typedef struct
{
    int key;
    char *otherinfo;
}ElemType;
//顺序表的存储结构                         
typedef struct
{
    ElemType *r;                                    //存储空间的基地址
    int  length;                                    //顺序表长度
}SqList;                                            //顺序表

void BInsertSort(SqList &L){
    //对顺序表L做折半插入排序
    int i,j,low,high,m;
    for(i=2;i<=L.length;++i)
    {
        L.r[0]=L.r[i];                              //将待插入的记录暂存到监视哨中
        low=1; high=i-1;                            //置查找区间初值
        while(low<=high)
        {                                           //在r[low..high]中折半查找插入的位置
            m=(low+high)/2;                         //折半
            if(L.r[0].key<L.r[m].key)  high=m-1;    //插入点在前一子表
            else  low=m+1;                          //插入点在后一子表
        }//while
        for(j=i-1;j>=high+1;--j)  L.r[j+1]=L.r[j];  //记录后移
        L.r[high+1]=L.r[0];                         //将r[0]即原r[i]，插入到正确位置
    }                                               //for
}                                                   //BInsertSort

void Create_Sq(SqList &L)
{
    int i,n;
    cout<<"请输入数据个数，不超过"<<MAXSIZE<<"个。"<<endl;
    cin>>n;                                         //输入个数
    cout<<"请输入待排序的数据：\n";
    while(n>MAXSIZE)
    {
        cout<<"个数超过上限，不能超过"<<MAXSIZE<<"，请重新输入"<<endl;
        cin>>n;
    }
    for(i=1;i<=n;i++)
    {
        cin>>L.r[i].key;
        L.length++;
    }
}

void show(SqList L)
{
    int i;
    for(i=1;i<=L.length;i++)
        cout<<L.r[i].key<<endl;
}

void main()
{
    SqList L;
    L.r=new ElemType[MAXSIZE+1];
    L.length=0;
    Create_Sq(L);
    BInsertSort(L);
    cout<<"排序后的结果为："<<endl;
    show(L);
}