A, B, C = map(int, input().split())

ans = 10 ** 10
for a in range(A + 1):
    for b in range(B + 1):
        for p in range(1, a + 10 * b + 1):
            ch = (a + 10 * b - p) // 10 + (a + 10 * b - p) % 10
            if ch + A - a + B - b == C:
                ans = min(ans, p)
if ans == 10 ** 10:
    print("Impossible")
else:
    print(ans)