A, B, C = [int(i) for i in input().split()]

mi = 1e10
for a in range(A + 10 * B + 1):
    for b in range(B + A // 10 + 1):
        if a + b == C and a + 10 * b <= A + 10 * B and a - A < 10:
            mi = min(mi, A - a + 10 * (B - b))

if mi > 1e9 or mi <= 0:
    print("Impossible")
else:
    print(mi)