(self)
return ret
:rtype: int
:rtype: int
: rtype : int
def next(self):
        """
        :rtype: int
        """
        v=self.queue.pop(0)
        ret=v.pop(0)
        if v: self.queue.append(v)
        return ret
def next ( self ) : v = self . queue . pop ( 0 ) ret = v . pop ( 0 ) if v : self . queue . append ( v ) return ret