A,B,C,D = map(int,input().split())
if D >= 10:
    print('Impossible')
    exit()
ans = 0
comb = 0
for i in range(B):
    ans += 50*2**(comb//100)
    comb += 1 

for i in range(A):
    ans += 100*2**(comb//100)
    comb += 1
print('Possible')
print(ans)