a,b,c,d=io.read("*n","*n","*n","*n")
if(10 <= d) then print("Impossible")
else
  score = 0
  base = 50
  while(100 <= b) do
    score = score + 100 * base
    base = base * 2
    b = b - 100
  end
  score = score + b * base
  arem = math.min(a, 100 - b)
  base = base * 2
  score = score + arem * base
  base = base * 2
  a = a - arem
  while(100 <= a) do
    score = score + 100 * base
    base = base * 2
    a = a - 100
  end
  score = score + a * base
  print("Possible")
  print(score)
end