Jane is 25 years old. Dick is older than Jane. In $$n$$ years, where $$n$$ is a positive integer, Dick's age and Jane's age will both be two-digit number and will have the property that Jane's age is obtained by interchanging the digits of Dick's age. Let $$d$$ be Dick's present age. How many ordered pairs of positive integers $$(d,n)$$ are possible?

(第二十届AIME1 2002 第3题)