#include<iostream>
using namespace std;
int BinarySearch(int a[],int n,int goal)
{
for(int i=0;i<=n;i++)
cout<<a[i]<<endl;
int mid,low=0,high=n;
while(low<=high)
{
mid=(low+high)/2;
if(goal==a[mid])
return mid;
else if(goal<a[mid])
high=mid-1;
else
low=mid+1;
}
return -1;
}
int main()
{
int arr[10]={0,3,7,9,11,35,66,78,89,100};
int a;
while(cin>>a)
{
int b;
b=BinarySearch(arr,9,a);
cout<<b<<endl;
}
return 0;
}
//非递归算法
int BinarySearch()
{
int low=0,high=n-1;
int temp;
while(low<=high)
{
temp=(low+high)/2;
if(k==R[temp])
{
return temp;
}
else if(k<R[temp])
{
high=temp-1;
}
else
{
low=temp+1;
}
}
return -1;
}
