a, b, c = map(int, input().split())

for yen in range(1, a + b * 10 + 1):
    for i in range(a + 1):
        for j in range(b + 1):
            if i + 10 * j < yen:
                continue
            d = (i + 10 * j) - yen
            cnt = a - i + b - j + d // 10 + d % 10
            if cnt == c:
                print(yen)
                exit()
                
print('Impossible')