c++实现顺序查找，折半查找

#include<stdio.h>
#include<iostream>
using namespace std;

#define LIST_INIT_SIZE 100
#define LISTINCREMENT 10
#define ElemType int

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

//建顺序表
void InitList_Sq(SqList &L)
{
L.elem = (ElemType *)malloc(LIST_INIT_SIZE*sizeof(ElemType));
if (!L.elem) cout << "存储分配失败!" << endl;
L.length = 0;
L.listsize = LIST_INIT_SIZE;
}

//在第i位置插入元素e
void ListInsert_Sq(SqList &L, int i,ElemType e)
{
int *newbase;
if (i<1 || i>L.length + 1) cout << "位置错误!" << endl;
if (L.length >= L.listsize)
{
newbase = (ElemType *)realloc(L.elem, (L.listsize + LISTINCREMENT)*sizeof(ElemType));
if (!newbase) cout << "重新分配地址错误!" << endl;
L.elem = newbase;
L.listsize += LISTINCREMENT;
}
int *p, *q;
q = &(L.elem[i - 1]);
for (p = &(L.elem[L.length - 1]); p >= q; --p)	//将第i位置及其以后的元素后移一个位置
*(p + 1) = *p;
*q = e;
++L.length;
}

//比较两个元素是否相等
int EQ(int a, int b)
{
if (a == b) return 1;
else return 0;
}

//顺序查找
void Search_Sq(SqList L, ElemType key)
{
int *p,i=1;
p = L.elem;
while (i <= L.length && L.elem[i-1]!=key) ++i;
if (i > L.length-1) cout << "不存在元素" << key << endl;
else
cout <<"顺序查找：元素"<< key << "的位置是：" << i << endl;
}

//折半查找
void Search_Bin(SqList L, ElemType key)
{
int low, high, mid;
low = 0;
high =L.length - 1;

while (low <high)
{
mid = (low + high) / 2;
if (EQ(key,L.elem[mid])) { cout << "折半查找：元素" << key << "的位置为：" << mid + 1 << endl; break; }
else
if (key < L.elem[mid])
{
high = mid - 1;
}
else
{
low = mid + 1;
}
}
}

void PrintL(SqList &L)
{
int i = 0;
while (i < L.length)
{
cout << L.elem[i]<<" ";
i++;
}
cout << endl;
}

void main()
{

SqList L;

//创建顺序表La并插入数据
InitList_Sq(L);
ListInsert_Sq(L, 1, 12);
ListInsert_Sq(L, 2, 25);
ListInsert_Sq(L, 3, 39);
ListInsert_Sq(L, 4, 56);
ListInsert_Sq(L, 5, 78);
ListInsert_Sq(L, 6, 80);
ListInsert_Sq(L, 7, 86);
ListInsert_Sq(L, 8, 88);
ListInsert_Sq(L, 9, 91);
ListInsert_Sq(L, 10, 95);
ListInsert_Sq(L, 11, 98);
ListInsert_Sq(L, 12, 99);
cout << "La的元素为：";
PrintL(L);

//顺序查找
Search_Sq(L, 91);

//折半查找
Search_Bin(L, 91);

//防止运行结果一闪而过
system("pause");
}