Question

求文档: 功能:下面函数为二分法查找key值。数组中元素已递增排序,

-------------------------------------------------------*/
#include <stdio.h>
fun(int a[],int n,int key)
{
int low,high,mid;
low=0;
high=n-1;
/***********SPACE***********/
while()
{
mid=(low+high)/2;
if(key<a[mid])
/***********SPACE***********/
【?】;
else if(key>a[mid])
/***********SPACE***********/
【?】;
else
/***********SPACE***********/
【?】;
}
return -1;
}
main()
{
int a[10]={1,2,3,4,5,6,7,8,9,10};
int b,c;
b=4;
c=fun(a,10,b);
if(c==1)
printf("not found");
else
printf("position %d\n",c);
}

Answer 1

//不好意思 第一个开始时没看见
fun(int a[],int n,int key)
{
int low,high,mid;
low=0;
high=n-1;
/***********SPACE***********/
while(low<=high)
{
mid=(low+high)/2;
if(key<a[mid])
/***********SPACE***********/
high=mid-1;
else if(key>a[mid])
/***********SPACE***********/
low=mid+1;
else
/***********SPACE***********/
return mid;
}
return -1;
}