a, b = map(int, input().split())
answer = min(((a - a // 2) - a // 2) * b, ((b - b // 2) - b // 2) * a)
print(answer)
15852da39205ea53635499015e1c351f693f7e97
<mask token>

<mask token>
print(answer)

a, b = map(int, input().split())
answer = min((a - a // 2 - a // 2) * b, (b - b // 2 - b // 2) * a)
print(answer)

a, b = map(int, input().split())
answer = min(((a - a // 2) - a // 2) * b, ((b - b // 2) - b // 2) * a)
print(answer)