The secret code
After returning from the trip, Alex was unpleasantly surprised: his porch door had a new combination lock. Alex can not get into his house! Code lock contains disks, each of which can be in one of positions. There is only one correct position. Alex thoroughly inspected discs and by fingerprints and scratches determined the probability of each position for each disk. Now Alex has attempts to guess the correct code: if he fails, his vigilant neighbors will call the police, and Alex will have a hard time persuading cops that he is not a thief, but tried to get home. Help Alex to calculate the maximum probability of getting home, not to the police.
Input
The first line of input file contains three integers: , та .
Next lines contain integers each: -th number -th line () – the probability of a situation where -th disc's correct position is . Given that .
Output
Print a single number – Alex's chances to guess the correct code in time. Output result should have an absolute percentage error not grater than .