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) combo = B for i in range(combo, combo + A): score.append(2**(i // 100) * 100) ans = sum(score) print(ans)