I know solution that gets AC with parameter EPS from 1e-0 to 1e-15 (1e+1 and 1e-16 get WA). It is _very_ strange that tests allow such inaccuracy.

It depends on the way use solve the problem. If you do all calculations in integers, any EPS from 1e-0 to 1e-15 will give right answer =)

How can you do all calculations in integers if there are a lot of real numbers in input and no limits on number of digits after decimal point?