代码

int binary_search(const unsigned *a, int n, unsigned x)
{
	int l=0,r=n-1,mid=0,Block=10000;
while(r-l>Block)
{
mid=l+(r-l>>1);
(a[mid]<x)?l=mid+1:r=mid;
}
for(int i=l;i<=r;i++)
if(a[i]==x)
return i;
}

评测结果