a, b, c, d = map(int, input().split())
l = 1000
c = 0
if d >= 10:
    print('Impossible')
    exit()
X = [1]*b+[0]*a
ans = 0
for x in X:
    if x == 1:
        c += 1
        ans += pow(2, (c-1)//100)*50
    else:
        c += 1
        ans += pow(2, (c-1)//100)*100
print('Possible')
print(ans)