a, b, _, d = map(int, input().split()) if d >= 10: print("Impossible") else: print("Possible") score = 0 cnt = 0 for _ in range(b): score += 50 * (2**(cnt//100)) cnt += 1 for _ in range(a): score += 100 * (2**(cnt//100)) cnt += 1 print(score)