线性表实现插入和删除

                 

/*
   线性表实现插入和删除

*/


#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>

#define LIST_INIT_SIZE 100
#define LISTINCRMENT 10
#define ElemType int

typedef struct{
    ElemType *elem;
    int       length;
    int       listsize;
}SqList;

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(OVERFLOW);
    L.length = 0;
    L.listsize = LIST_INIT_SIZE;
    return true;
}     //InitLst_Sq

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
     //i的合法值为1 <= i <= ListLength_Sq(L)+1
     ElemType *newbase,*q,*p;
     if(i < 1||i > L.length + 1)      //i不合法
        return false;
     if(L.length >= L.listsize){      //当前存储空间已满，添加分配
         newbase = (ElemType *)realloc(L.elem,
                            (L.listsize+LISTINCRMENT)*sizeof(ElemType));
         if(!newbase)                 //存储分配失败
            exit(OVERFLOW);
         L.elem = newbase;           //新地址
         L.listsize += LISTINCRMENT;   //添加存储容量
     }
     q = &(L.elem[i-1]);               //q为插入位置
     for(p = &(L.elem[L.length-1]);p >= q;--p)
        *(p+1) = *p;

     *q = e;                         //插入e
     ++L.length;                       //表长加一
     return true;
}   //ListInsert_Sq

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
    ElemType *p,*q;
    if((i < 1)||(i > L.length))
        return false;
    p = &(L.elem[i-1]);
    e = *p;
    q = L.elem + L.length - 1;
    for(++p;p <= q;++p)
        *(p-1) = *p;
    --L.length;
    return true;
}//ListDelete_Sq

int main()
{
    int i;
    SqList L;
    puts("Please input 5 num:");
    if(InitList_Sq(L)){
        //创建新表。输入五个元素
        for(i = 0;i < 5;i++){
            scanf("%d",&L.elem[i]);
            ++L.length;
        }
        for(i = 0;i < 5;i++){
            printf("%d ",L.elem[i]);
        }
        puts("");
    }
    else{
        puts("ERROR");
        exit(OVERFLOW);
    }

    //插入元素,要插入的位置和元素值
    puts("Please Input You Insert num ans possition:");
    int pos,num;
    scanf("%d%d",&num,&pos);
    if(ListInsert_Sq(L,pos,num)){
        printf("Insert After:
");
        for(i = 0;i < L.length;++i)
            printf("%d ",L.elem[i]);
        printf("
");
    }
    else{
        puts("Delete Error");
        exit(OVERFLOW);
    }
    //删除元素。要删除元素的位置
    puts("Please Input You want to Delete possition:");
    scanf("%d",&pos);
    if(ListDelete_Sq(L,pos,num)){
        printf("Delete After:
");
        for(i = 0;i < L.length;++i)
            printf("%d ",L.elem[i]);
        puts("");
    }
    else
        puts("Delete Error");
    return 0;
}