all_data = readlines
our_price = all_data[0].to_i
other_price = all_data[1].to_i
each_loss = our_price + other_price
booking_num = all_data[2].to_i
booked_rooms = all_data.shift(2)
total_loss = 0

duplicated_booked_rooms = booked_rooms.group_by{|i| i}.reject{|k,v| v.one?}.keys
duplicated_booked_rooms.each do |room_num|
    num_of_duplicating = booked_rooms.count(room_num)
    total_loss += (num_of_duplicating - 1) * each_loss
end

print total_loss