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

cmax = A + 10 * B 
for cost in range(1,cmax+1):
    for a in range(A+1):
        for b in range(B+1):
            pay = a + 10 * b
            if pay < cost:
                continue
            q, r = divmod(pay-cost,10)

            if A - a + B - b + q + r == C:
                print(cost)
                exit()


print("Impossible")