Starting at $$(0,0),$$ an object moves in the coordinate plane via a sequence of steps, each of length one. Each step is left, right, up, or down, all four equally likely. Let $$p$$ be the probability that the object reaches $$(2,2)$$ in six or fewer steps. Given that $$p$$ can be written in the form $$m/n,$$ where $$m$$ and $$n$$ are relatively prime positive integers, find $$m+n.$$

(第十三届AIME1995 第3题)