It seems strange, but mushrooms like soda. Moreover, Michael likes to make experiments with it. Each kind of soda has it's own level of sweetness. Michael has n containers with soda of different levels. If Michael mix two containers with levels x and y, instead of these two he will get soda with level 2 * min(x,y).
Help Michael to get soda with the highest possible level of sweetness.
The first line contains the number of containers n (1 ≤ n ≤ 10^6
). The second line contains n integers: the level of sweetness x[i]
(-10^9
≤ x[i]
≤ 10^9
).
Print the highest possible level of sweetness that can be obtained by mixing some of the available sodas.