1 #include<iostream>
 2 #include<cstdio>
 3 using namespace std;
 4 int main() 
 5 {
 6     int m,n,i;
 7     double num;
 8     cin>>m;
 9     while(m--)
10     {
11         double sum=0;
12         cin>>n;
13         for(i=1;i<=n;i++)
14         {
15             num=i;
16             if(i%2==0)sum-=1/num;
17             //num=(i%2==0)?(-i):i;
18             else sum+=1/num;
19         }
20         printf("%.2lf\n",sum);
21     }
22     return 0;
23 }