4000 《数据结构》（严蔚敏）算法代码实现第二章

个人学习笔记

#define LIST_INIT_SIZE   100//线性表存储空间的初始分配量
#define LISTINCREMENT   10//线性表存储空间的分配增量
typedef char ElemType;
#define OK 1;
#define NO 0;
#define ERROR 0;
#include <iostream>
#include <stdlib.h>
#include <string.h>
using namespace std;
typedef struct
{
ElemType *elem;
int length;
int listsize;
}SqList;
bool compare(ElemType c1, ElemType c2)
{
if(c1 == c2)
return 1;
else
return 0;
}
bool InitList_Sq(SqList &L)//构造一个空的线性表L
{
L.elem = (ElemType *)malloc(LIST_INIT_SIZE * sizeof(ElemType));
if(!L.elem)
exit(1);//存储分配失败
L.length = 0;//空表长度为0
L.listsize = LIST_INIT_SIZE;//初始存储容量
return OK;
};
bool CreateList(SqList &L)//给一个空线性表赋初值
{
cout<<"请输入线性表的初值："<<endl;
cin>>L.elem;
//L.elem = "123456";
L.length = strlen(L.elem);
L.listsize = L.length;
return OK;
}
bool ListInsert_Sq(SqList &L,int i,ElemType e)//在顺序线性表L中第i个位置之前插入新的元素e,i的合法值为1<=i<=ListLength_Sq(L)+1
{
ElemType *newbase, *q, *p;
if(i<1 || i>L.length+1)
return ERROR;
if(L.length >= L.listsize)//当前存储空间已满，增加分配
{
newbase = (ElemType *)realloc(L.elem, (L.listsize+LISTINCREMENT)*sizeof(ElemType));
if(!newbase)
exit(1);//存储分配失败
L.elem = newbase;//新基址
L.listsize += LISTINCREMENT;//增加存储容量
}
q = &(L.elem[i-1]);
for(p=&(L.elem[L.length-1]); p>=q; --p)
*(p+1) = *p;//插入位置及以后的元素右移
*q = e;//插入e
ElemType *t = &(L.elem[L.length]);
*++t = '\0';
++L.length;//表长增1
return OK;
}
bool ListDelete_Sq(SqList &L, int i, ElemType &e)//在顺序线性表L中删除第i个元素，并用e返回其值
//i的合法值为1<=i<=ListInsert_Sq(L)
{
ElemType *p, *q;
if((i<1) || (i>L.length))
return ERROR;//i值不合法
p = &(L.elem[i-1]);
e = *p;//被删除的元素赋给e
q = L.elem+L.length-1;//表尾元素的位置
for(++p; p<=q; ++p)
*(p-1) = *p;//被删除元素之后的元素左移
*--p = '\0';//特别注意，此处需要自行清空最后一个值，否则最后一个值就会重复
--L.length;//表长减1
return OK;
}//ListDelete_Sq
int LocateElem_Sq(SqList L,ElemType e)//在顺序线性表L中查找第1个值与e相同的元素的位序
//若找到，则返回其在L中的位序，否则返回0
{
int i = 1;//i的初值为第1个元素的位序
ElemType *p = L.elem;//i的初值为第1个元素的位序
while((i<=L.length) && !(compare(*p++,e)))
++i;
if(i<=L.length)
return i;
else
return 0;
}//LocateElem_Sq
void MergeList_Sq(SqList La,SqList Lb,SqList &Lc)//已知顺序线性表La和Lb的元素按值非递减排列
//归并La和Lb得到新的顺序线性表Lc,Lc的元素也按值非递减排列
{
ElemType *pa = La.elem;
ElemType *pb = Lb.elem;
Lc.listsize = Lc.length = La.length+Lb.length;
ElemType* pc = Lc.elem = (ElemType *)malloc(Lc.listsize*sizeof(ElemType));
if(!Lc.elem)
exit(1);//存储分配失败
ElemType* pa_last = La.elem + La.length - 1;
ElemType* pb_last = Lb.elem + Lb.length - 1;
while(pa<=pa_last && pb<=pb_last)//归并
{
if(*pa <= *pb)
*pc++ = *pa++;
else
*pc++ = *pb++;
}
while(pa<=pa_last)
*pc++ = *pa++;//插入La的剩余元素
while(pb<=pb_last)
*pc++ = *pb++;//插入Lb的剩余元素
*pc = '\0';//添加以截断
}
void outputList(SqList &L)//输出函数
{
cout<<L.elem<<endl;
}
int main()
{
cout<<"创建一个线性表\n";
SqList La;
InitList_Sq(La);
CreateList(La);
cout<<"after insert"<<endl;
ListInsert_Sq(La, 2, '2');
outputList(La);
ElemType tmp;//创建一个临时变量
ListDelete_Sq(La, 3, tmp);
cout<<"after delete:"<<endl;
outputList(La);
SqList Lb, Lc;
InitList_Sq(Lb);
InitList_Sq(Lc);
CreateList(Lb);
MergeList_Sq(La, Lb, Lc);
cout<<"after merge:";
outputList(Lc);
int n = LocateElem_Sq(Lc,'7');
cout<<n<<endl;
return 0;
}