Check out this challenge:
(The competition has already ended, so I'm just curious about the Python solution, which the organizers refused to reveal, so this is not cheating in any way.)
I only managed to solve the challenge in 77 characters. (Talking only about Python here.) However, one adr2370 managed to solve the challenge in 66 characters!
Please help me find the 66-character solution! I'm very very curious because I had to work really hard to bring mine down to 77, and I'm amazed as to how someone came up with a 66-character solution.
For reference, my solution:
for j in'x'*input():print'%.15f'%sum((-1)**i/(2.*i+1)for i in range(input()))