Solve the CodeSprint4 Leibniz code golf challenge in Python in 66 characters

Python, 65 characters

exec'print`sum((-1.)**x/(x-~x)for x in range(input()))`;'*input()

Python 71 bytes

exec"print'%.15g'%sum((-1.)**i/(i-~i)for i in range(input()));"*input()

Not quite 66 bytes, but with a score of 22.90, it would have ranked second overall.

Edit: regarding Ari's comment about the 66 byte Python solution being a 'hack', I don't think that's exactly what happened. I've noticed several times that the submitted language is displayed incorrectly. For example here: Baconian Cipher. This challenge may only be submitted in Brainf_ck, yet the second ranked solution was submitted in Python 2 (interestingly enough, spot 23 is also Python 2. If I were to speculate, I would say that if the language information is missing from a submission for whatever reason, it seems to default to Python).

I suspect that a similar error may have occurred here, and that the shortest Python solution submitted during the challenge was actually 72 bytes.

Update: After speaking with a moderator, it seems that Ari was right: