#include<stdio.h>
int main(void)
{
int i,n,m,denominator,flag,b;
double sum,item;
scanf("%d",&m);
for(i=1;i<=m;i++){
sum=0;
flag=1;
denominator=1;
scanf("%d",&n);
for(b=1;b<=n;b++){
item=flag*1.0/denominator;
sum=sum+item;
flag=-flag;
denominator=denominator+1;}
printf("%.2lf
",sum);
}
return 0;
}