def calc(): A,B,C,D =map(int,input().split()) if D >= 10: print("impossible") return score = 0 for num,sco in zip([A+B,B],[100,-50]): plus = sco for i in range(8): if num -100*i < 101: score += (num -100*i)*plus break else: score += 100*plus plus *= 2 print("possible") print(score) calc()