The bitwise, boolean and conditional operators: & | ^ && || &= |= ^= &&= ||= << >> <<= >>= ?: are not available in POSIX bc.
Bitové, boolovské a podmíněné operátory: & | ^ && || ^^ &= |= ^= &&= ||= ^^= << >> <<= >>= ?: …nejsou v POSIX bc dostupné.