RANDMOD  Random modulo n
Kubík went to buy a pizza. To his surprise, the pizza box was made out of recycled… punch cards!
With his eagle eye, he deciphered the program the punch cards described:
n = read_input();
ans = 0;
while(n > 0)
{
ans = ans + 1;
n = random() % n;
}
random() is a function which returns uniformly random nonnegative integers, and % is the modulus operator.
Now he wonders what the expected value of ans would be for a given initial value of n, and he is unable to enjoy his pizza until someone computes the answer for him.
Input
The first line contains an integer 1 ≤ T ≤ 5  the number of test cases.
Each of the next T lines contain a single integer n, where 1 ≤ n ≤ 300 000. The sum of n within an input file won't exceed 300000.
Output
Output the expected value of the variable ans – that is, the sum of v × (probability that ans will end up with value v), for all possible values v.
Your answer will be considered correct if the absolute or relative error does not exceed 10^{−9}. Make sure to print enough decimal places.
Example
Input:
2
2
47
Output:
1.5
4.4379638417
In the first case, either random()%2 = 0 with probability 1/2, which leads to ans = 1, or random()%2 = 1 with probability 1/2, after which we certainly get random()%1 = 0, so ans = 2. Expected value of ans is therefore 1 × 1/2 + 2 × 1/2 = 1.5.
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baraniec:
20190802 11:26:19
It works fine now. AC finally. Very nice problem anyway! 

hodobox:
20190802 01:58:05
Unfortunately, a recent update in SPOJ's compiler killed my judge. I removed it from classical temporarily until I fixed the issue. It seems to now have been fixed  anyone affected please resubmit your solution to get a different result than Internal Error :).

Added by:  Hodobox 
Date:  20190527 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  own problem 