After discovering the normalized probabilities, Kevin Yang was awarded the Nobel Prize for mathematics.
With this discovery, Kevin can solve even more combinatorics problems.
One of the combinatorics problems entails a list of events that each have a normalized probability of occurring.
Since these are normalized probabilities, there are types of probability:
A
corresponds to a 100% probability of occurring.B
corresponds to an 80% probability of occurring.C
corresponds to a 60% probability of occurring.D
corresponds to a 40% probability of occurring.E
corresponds to a 20% probability of occurring.
Kevin wants to know how likely it is that all these events occur (assuming each event is independent) up to an error of .
Constraints
A
B
C
D
E
Input Specification
The first line will contain , the number of independent events.
The next lines will contain , one of the normalized probabilities (A
, B
, C
, D
, or E
).
Output Specification
Output the probability of all events occurring up to an error of .
Sample Input 1
3
A
B
B
Sample Output 1
0.640000
Sample Input 2
4
B
C
D
E
Sample Output 2
0.038400
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