查补查找(二分查找的优化)

int insertsearch(int num[],int n)
{
int low,mid,high;
low=1;
hign=N;
while(low<=high)
{/////下面是关键点//////
mid=(high-low)*(n-num[low])/(num[high]-num[low])+low;
if(mid<low || mid>high)
return 0;
if(n<num[mid])
high=mid-1;
else if(n>num[mid])
low=mid+1;
else
return mid;
}
return 0;
}