#!/usr/bin/env python3

import itertools
import sys


INF = sys.maxsize


def solve(a, b, c):
    res_money = INF
    for num_one, num_ten in itertools.product(range(a + 1), range(b + 1)):
        if num_one == num_ten == 0:
            continue
        max_item_money = num_one + 10 * num_ten
        for item_money in range(1, max_item_money + 1):
            change = max_item_money - item_money
            change_ten, change_one = divmod(change, 10)
            num_coins = a - num_one + change_one + b - num_ten + change_ten
            if num_coins == c:
                res_money = min(res_money, item_money)
                break
    return res_money


def main():
    a, b, c = (int(z) for z in input().split())
    res = solve(a, b, c)
    print(res if res < INF else "Impossible")


if __name__ == "__main__":
    main()