Christmas eve!

On the Christmas Eve, Santa was in a hurry to distribute gifts, so he asked the most innocent child in the country to help him in distributing 10 gifts to 10 different houses, where each house receives a gift.

To House #1, the boy gave the gift of House #2. At the end of the day, Santa informed the boy that he had not distributed a single gift to the correct place.

In how many ways can this happen?

Ignore the order in which the gifts were distributed. Consider just which gifts the houses received.


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