A,B,C,D = map(int,input().split())
if D>=10:
    print('Impossible')
else:
    print('Possible')
    score = 0
    combo = 0
    bonus = 1
    for i in range(B):
        combo+=1
        score+=2**((combo-1)//100)*50
    for i in range(A):
        combo+=1
        score+=2**((combo-1)//100)*100
    print(score)