数据结构9-关于折半查找的实例

程序实现用折半查找的查找方法查找给定数组中的元素，代码如下所示：

#include"stdio.h"bin_search(int A[],int n,int key){int low,high,mid;low=0;high=n-1;while(low<=high){mid=(low+high)/2;if(A[mid]==key)return mid; /*查找成功，返回mid*/if(A[mid]<key){low=mid+1; /*在后半序列中查找*/}if(A[mid]>key){high=mid-1; /*在前半序列中查找*/}}return -1; /*查找失败，返回-1*/}main(){int A[10] = {2,3,5,7,8,10,12,15,19,21},i,n,addr;printf("The contents of the Array A[10] are\n");for(i=0;i<10;i++)printf("%d ",A[i]); /*显示数组A中的内容*/printf("\nPlease input a interger for search\n");scanf("%d",&n); /*输入待查找的元素*/addr = bin_search(A,10,n); /*折半查找，返回该元素在数组中的下标*/if(-1 != addr) /*查找成功*/printf("%d is at the %dth unit is array A\n ",n,addr);elseprintf("There is no %d in array A\n",n); /*查找失败*/getche();}

 

实现的结果如下图所示：