a, b, c, d = map(int, input().split())

num, score = 0, 0

if d >= 10:
    print("Impossible")
else:
    for i in range(b):
        score += 50 * 2 ** (num // 100)
        num += 1

    for i in range(a):
        score += 100 * 2 ** (num // 100)
        num += 1
        
    print("Possible")
    print(score)