main = do
  li <- getLine
  let [a,b,c] = map read $ words li
  print $ compute a b c

-- 偶数があれば0
-- 全て奇数なら、小さい方ふたつの積
-- 手抜きするとオーバーフロー

compute :: Int -> Int -> Int -> Int
compute a b c
  | even a || even b || even c = 0
  | True = x * y
  where
    x = minimum [a,b,c]
    z = maximum [a,b,c]
    y = sum [a,b,c] - z - x
