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

okn = a+b*10

for i in range(1,okn+1):
    for j in range(a+1):
        for k in range(b+1):
            if i <= j+k*10:
                tmp = j+k*10-i
                if tmp%10+tmp//10+a-j+b-k == c:
                    print(i)
                    exit()

    

print("Impossible")