A, B, C = map(int, input().split())
INF = 10**9
ans = INF
for a in range(A+1):
    for b in range(B+1):
        K = a+b*10
        for k in range(1, K+1):
            oturi = K-k
            cnt = oturi//10
            cnt += oturi%10
            cnt += (A-a)
            cnt += (B-b)
            if cnt==C:
                ans = min(ans, k)
if ans==INF:
    print("Impossible")
else:
    print(ans)