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