A, B, C, D = map(int, input().strip().split())

if D >= 10:
  print('Impossible')
  exit(0)

print('Possible')

score = []

for i in range(B):
  score.append(2**(i // 100) * 50)

print('score:{}'.format(score))
combo = B

for i in range(combo, combo + A):
  score.append(2**(i // 100) * 100)

print('score:{}'.format(score))

ans = sum(score)
print(ans)