A, B, C, D = map(int, input().split())
if D == 10:
    print('Impossible')
else:
    score = 0
    count = 0
    for i in range(B):
        count += 1
        score += 50 * 2**((count - 1) // 100)
    for i in range(A):
        count += 1
        score += 100 * 2**((count - 1) // 100)
    print('Possible')
    print(score)