数据结构 顺序查找和二分查找

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/*
Sequential Search
*/
#include<stdio.h>
#include<string.h>
#include<string>
#include<iostream>
#include<algorithm>
#include<math.h>
#include<stack>
using namespace std;
int Sequential_Search(int a[],int n,int key)//普通顺序查找
{
    int i;
    for(i=0; i<n; i++)
    {
        if(a[i]==key)return i;
    }
    return -1;
}

int Sequential_Search2(int a[],int n,int key)
{//优化顺序查找，将数组最后一个设为"哨兵",这样就不用判断越界了(也可以将哨兵设在数组开头的位置)
    int i=0;
    a[n]=key;
    while(a[i]!=key)
    {
        i++;
    }
    if(i==n)return -1;
    else return i;
}

int binarySearch(int a[],int n,int key)//二分查找
{
    int low=0,high=n-1;
    while(low<=high)
    {
        int mid=(low+high)/2;
        if(a[mid]>key)high=mid-1;
        else if(a[mid]<key)low=mid+1;
        else return mid;
    }
    return -1;
}
int main()
{
    int a[]={0,5,73,8,9,2,10};

    printf("%d\n",Sequential_Search(a,7,73));
    sort(a,a+7);
    for(int i=0;i<7;i++)printf("%d ",a[i]);
    printf("\n");
    printf("%d\n",binarySearch(a,7,10));


    return 0;
}