查找（问题代码）

#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<time.h>
#include<algorithm>
#include<iostream>
using namespace std;

#define overflow -2
#define EQ(a,b) ((a)==(b))
#define LT(a,b) ((a)<(b))
#define LQ(a,b) ((a)<=(b))
typedef int KeyType;
#define maxsize 20
typedef struct {
    KeyType key;
}RedType;

typedef struct {
    RedType *r;
    int length;
}SqList;
void InitList_Sq(SqList &L)
{
    L.r=(RedType *)malloc((maxsize+1)*sizeof(RedType));
    if(!L.r)  exit(overflow);
    L.length=0;
}
int search_Seq(SqList L,KeyType key)
{
    int i;
    L.r[0].key=key;
    for(i=L.length;!EQ(L.r[i].key,key);--i);
    return i;
}
int search_Bin(SqList L,KeyType key)
{
    int low,high,mid;
    low=1;high=L.length;
    while(low<=high)
    {
        mid=(low+high)/2;
        if(EQ(key,L.r[mid].key))    return mid;
        else if(LT(key,L.r[mid].key))   high=mid-1;
        else    low=mid+1;
    }
    return 0;
}

void InsertSort(SqList &L)
{
    int i,j;
    for(i=2;i<=L.length;++i)
        if(LT(L.r[i].key,L.r[i-1].key))
    {
        L.r[0].key=L.r[i].key;
        for(j=i-1;LT(L.r[0].key,L.r[j].key);--j)
            L.r[j+1].key=L.r[j].key;
        L.r[j+1].key=L.r[0].key;
    }
}

void BubbleSort(SqList &L)
{
    int i,j;
    KeyType temp;
    for(i=L.length-1;i>=1;--i)
        for(j=1;j<=i;j++)
            if(LT(L.r[j+1].key,L.r[j].key))
    {
        temp=L.r[j+1].key;
        L.r[j+1].key=L.r[j].key;
        L.r[j].key=temp;
    }
}

int partition(SqList &L,int low,int high)
{
    KeyType pivotkey;
    L.r[0].key=L.r[low].key;
    pivotkey=L.r[low].key;
    while(low<high)
    {
        while(low<high && L.r[high].key>=pivotkey)  --high;
        L.r[low].key=L.r[high].key;
        while(low<high && L.r[low].key<=pivotkey) ++low;
        L.r[high].key=L.r[low].key;
    }
    L.r[low].key=L.r[0].key;
    return low;
}

void QSort(SqList &L,int low,int high)
{
    int pivotloc;
    if(low<high)
    {
        pivotloc=partition(L,low,high);
        QSort(L,low,pivotloc-1);
        QSort(L,pivotloc+1,high);
    }
}

void QuickSort(SqList &L)
{
    QSort(L,1,L.length);
}

void SelectSort(SqList &L)
{
    int i,j,k;
    KeyType temp;
    for(i=1;i<L.length;++i)
    {
        j=i;
        for(k=i+1;k<=L.length;++k)
        {
            if(LT(L.r[k].key,L.r[j].key))
                j=k;
        }
        if(i!=j)
        {
            temp=L.r[i].key;
            L.r[i].key=L.r[j].key;
            L.r[j].key=temp;
        }
    }
}
void ListGenRand(SqList &L,int n,unsigned k)
{
    int i;
    L.length=0;
    srand((unsigned)time(0)+k);
    for(i=1;i<=n;i++)
    {
        L.r[i].key=rand()%100;
        ++L.length;
    }
}

void DispList(SqList L)
{
    int i;
    for(i=1;i<=L.length;i++)
        printf("%2d ",L.r[i].key);
    printf("\n");
}

int main()
{
    SqList L;
    int n,num;
    unsigned k=0;
    KeyType key;

    InitList_Sq(L);

    srand((unsigned)time(0));
    n=!+rand()%maxsize;
    printf("随机产生元素个数为：%d\n",n);
    ListGenRand(L,n,++k);
    printf(" 顺序查找表：");
    DispList(L);
    printf(" 请输入待查找的关键字值：");
    scanf("%d",&key);

    printf("顺序查找表结果：");
    num=search_Seq(L,key);
    if(num) printf("查找成功！第%d个元素。\n",num);
    else printf("查找不成功！\n");

    SelectSort(L);
    printf(" 折半查找表：");
    DispList(L);
    printf("折半查找结果：");
    num=search_Bin(L,key);
    if(num)printf("查找成功！第%d个元素。\n",num);
    else printf("查找不成功！\n");
    printf("\n");

    printf("插入排序结果：\n");
    ListGenRand(L,n,++k);
    printf("    排序前：");
    DispList(L);
    InsertSort(L);
    printf("  排序后：");
    DispList(L);

    printf("冒泡排序结果：\n");
    ListGenRand(L,n,++k);
    printf("    排序前：");
    DispList(L);
    BubbleSort(L);
    printf("  排序后：");
    DispList(L);

    printf("快速排序结果：\n");
    ListGenRand(L,n,++k);
    printf("    排序前：");
    DispList(L);
    QuickSort(L);
    printf("  排序后：");
    DispList(L);

    printf("选择排序结果：\n");
    ListGenRand(L,n,++k);
    printf("    排序前：");
    DispList(L);
    SelectSort(L);
    printf("  排序后：");
    DispList(L);
    return 0;
}