a,b,c,d=map(int,input().split())
if d>=10:
    print('Impossible')
    exit()
p=[]
for i in range(a):
    p.append(100)
for i in range(b):
    p.append(50)
ans=0
p.sort()
tap=1
for i in range(len(p)):
    ans+=tap*p[i]
    if i%100==99:
        tap*=2
print('Possible')
print(ans)