线性表的顺序表示和实现

#include<bits/stdc++.h>//c++万能头文件，写了这个其他头文件不用写 
using namespace std;//使用名字空间，你不用管 

#define List_Init_Size 100
#define List_Inrement 10
#define pr printf

struct List{
    int *elem;//表的基地址 
    int length;//当前表长 
    int listsize;//当前表的容量 
};

//初始化线性表 
bool InitList(List &L)
{
    L.elem = (int *)malloc(List_Init_Size*sizeof(int));
    if(L.elem == NULL) exit(-1); //如果分配内存失败，就退出程序
    
    L.length = 0;
    L.listsize = 100; 
    return 1;
} 

//线性表插入元素 
bool ListInsert(List &L,int i,int e)
{
    if(i < 1 || i > L.length + 1) 
    {
        puts("Oh! Baby! The insertion position is invalid. Please re-enter the insertion position!");
        return 0;
    } 
    //需要清楚，下标是从0开始，
    //该函数实现的是在第i个元素前面插入一个元素，所有必须判断插入位置的合法性 
    //除了插在最后的元素后面外其他都需要把后面的元素往后移动
    
    if(L.length >= L.listsize)
    {
        //表的容量不够，因为插入的会增加一个元素所以有等号 。
        //增加容量
        int *newbase = (int *)realloc(L.elem,(List_Init_Size + List_Inrement)*sizeof(int));
        //realloc函数用来为ptr重新分配大小为size的一块内存，看似很简单，
        //在使用过程中却会发生各种错误。
        //函数形式为：
        //void * realloc ( void * ptr, size_t new_size ); 
        
        if(newbase == NULL)
        {
            //意味着重新分配内存失败
            puts("Sorry Baby! Reassigning memory failed!");
            exit(-1);//退出程序 
        }
        L.elem = newbase;
        L.listsize += List_Inrement;
    } 
    
    int *q = L.elem + (i-1);//获取第i个元素的地址 
    
    //第i的后面元素往后移动 
    for(int *p = L.elem + (L.length-1); p >= q; p--) 
    *(p+1) = *p;
    
    *q = e;
    ++L.length;//添加一个元素，长度加一 
    return 1;
}

//线性表删除元素 
bool List_Delete(List &L,int i,int &e)
{
    //先判断位置是否合法
    if(i < 1 || i > L.length) 
    {
        puts("Oh baby! The deletion location is illegal, please re-enter!");
        return 0;
    }
    int *q = L.elem + (L.length - 1);
    int *p = L.elem + (i-1); 
    e = *p;
    ++p;//这里是为了把第I后面的元素往前移动，此时的p为第i+1个元素的位置 
    for(p; p <= q; p++)
    *(p-1) = *p;
    --L.length;//删除一个元素，长度减一
    return 1; 
} 

//获取线性表当前的元素个数
int getListLength(List &L)
{
    return L.length;
} 

//获取线性表元素 
bool getElem(List &L,int q,int &e)
{
    if(q < 1 || q > L.length)
    {
        puts("Oh! Baby! The  position is invalid. Please re-enter the position!");
        return 0;
    }
    int *p = L.elem;
    e = *(p + (q - 1)); 
    return 1;
}

//遍历线性表 
void List_Traver(List &L)
{
    puts("Let's do it! Traver! Traver_List!"); 
    int *p = L.elem;
    for(p; p <= L.elem + (L.length - 1); p++)
    cout << *p << " ";
    puts("");
}
 
//获取要查找的第一个满足某个比较关系的元素位置,我就判断大于，小于，等于吧 
int LocateElem(List &L,int e,string s)
{
    int *p = L.elem;
    int len = L.length;
    int now = 1;
       if(s == ">")
    {
           for(p ;p <= L.elem + (len - 1);p++)
           {
               if(*p > e)
               {
                   return  now;
            }
            now++;
        }
        puts("Oh baby! Sorry, there is no such number!");
        return 0;
    } 
    else if(s == "<")
    {
        for(p ;p <= L.elem + (len - 1);p++)
           {
               if(*p < e)
               {
                   return  now;
            }
            now++;
        }
        puts("Oh baby! Sorry, there is no such number!");
        return 0;
    }
    else{
        for(p ;p <= L.elem + (len - 1);p++)
           {
               if(*p == e)
               {
                   return  now;
            }
            now++;
        }
        puts("Oh baby! Sorry, there is no such number!");
        return 0;
    }
} 
//销毁线性表,清除堆内存。防止内存泄露 
void List_Destroed(List &L)
{
    int *p;
    //只能从后面销毁 
    for(p = L.elem + (L.length - 1); p >= L.elem; p--)
    {
        free(p); 
    }
}


int main()
{
    List L;
    int ok = InitList(L);
    if(ok)
    {
        puts("Oh Yes! Linear table created successfully!");
        cout << "base address = " << L.elem << endl;
        cout << "L.length =  " << L.length << endl;
        cout << "L.listsize = "<< L.listsize << endl;
    } 
    
    for(int i = 1;i <= 10;i++)
    {
        if(ListInsert(L,i,i))
        {
            puts("GO");
        }
        else {
            puts("Something Wrong!");
            exit(-1);
        }
    }
    
    puts("Check the creation of a linear table");
    cout << "base address = " << L.elem << endl;
    cout << "L.length =  " << L.length << endl;
    cout << "L.listsize = "<< L.listsize << endl;
    
    List_Traver(L);
    
    int selem;
    bool flag = getElem(L,7,selem);
    if(flag)
    {
        cout << "7th number is equal to " << selem << endl;
    }
    int pos = LocateElem(L,5,"<");
    if(pos) {
        cout << pos << endl;
    }
    
    pos = LocateElem(L,5,"=");
    if(pos) {
        cout << pos << endl;
    }
    
    pos = LocateElem(L,5,">");
    if(pos) {
        cout << pos << endl;
    }
    
    cout << "sizeof(L) = " << sizeof(L) << endl;
    List_Destroed(L);//销毁 
    cout << "sizeof(L) = " << sizeof(L) << endl;//检查是否销毁成功，如果成功，
    //下面的语句就不执行 ，因为销毁之后不可用了。 
    List_Traver(L); 
    return 0;
}