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

min_price = float('inf')

for x in range(A + 1):
    for y in range(B + 1):
        S = x + 10 * y
        if S == 0:
            continue
        D = C - (A + B) + x + y
        if D < 0:
            continue
        # Find maximum k <= S where (k//10 + k%10) == D
        max_k = -1
        for k_candidate in range(S, -1, -1):
            sum_coins = (k_candidate // 10) + (k_candidate % 10)
            if sum_coins == D:
                max_k = k_candidate
                break
        if max_k == -1:
            continue
        p = S - max_k
        if p <= 0:
            continue
        if p < min_price:
            min_price = p

if min_price != float('inf'):
    print(min_price)
else:
    print("Impossible")