a, b, c, d = gets.split.map &:to_i
if d > 9
  puts "Impossible"
else
  s = 0
  x = 1
  u = 0
  b.times do
    s += x * 50
    u += 1
    x *= 2 if u % 100 == 0
  end
  a.times do
    s += x * 100
    u += 1 
    x *= 2 if u % 100 == 0
  end
  puts "Possible"
  puts s
end