# mp3 Shuffling

When a mp3 is on shuffle, after a song ends the mp3 player will choose a song at random and play it, the mp3 will not play the same song twice in a row.

Yan Yau has 10 distinct songs on his mp3. One day he goes on his mp3 and listens to 5 song on shuffle. The probability that all the songs he listened to are distinct can be expressed as $$\frac mn$$ where $$m$$ and $$n$$ are positive coprime integers. Find the value of $$\left\lfloor \frac{m+n}{1000}\right\rfloor$$.

Details and Assumptions

$$\left\lfloor x\right\rfloor$$ is the floor function. $$\left\lfloor x\right\rfloor$$ Is the largest integer not greater than $$x$$. For example: $$\left\lfloor 3\right\rfloor = 3$$, $$\left\lfloor 5.8\right\rfloor =$$, $$\left\lfloor \pi \right\rfloor = 3$$

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