a, b, c = map(int, input().split())
ans = 10**18
for i in range(a+1):
    for j in range(b+1):
        x = i+10*j
        if x == 0:
            continue
        R = a-i+b-j
        for y in range(1, x+1):
            z = x-y
            q, r = divmod(z, 10)
            if R+q+r == c:
                ans = min(ans, y)
if ans != 10**18:
    print(ans)
else:
    print('Impossible')