A,B,C = map(int,input().split())
for g in range(1,A+B*10+1):
    for a in range(A+1):
        for b in range(B+1):
            Pay = a + 10 * b
            if Pay < g:
                continue
            Back = Pay - g
            if A + B - a - b + (Back // 10) + (Back % 10) == C:
                print(g)
                exit()
print('Impossible')