def f(a):
    if a >= 10:
        a = a // 10 + a % 10
    return a
def solve():
    a, b, c = map(int, input().split())
    if a <= c:
        if b == 0:
            return "Impossible"
        if c - a > (b - 1) + 9:
            return "Impossible"
    if b < c:
        return f(a - (c - b)) if a >= 10 else a - (c - b)
    else:
        return f(a + (b - c) * 10) if a >= 10 else a + (b - c) * 10
print(solve())