5675脑筋急转弯困难数值题medium
Seating with Forbidden Own-Chair
题目
Four people, each with an assigned chair, are reseated so that no person sits in their own assigned chair, and additionally person 1 must not sit in chair 2. How many seatings are valid?
解题计时
0:00
提交作答时记录，用于后续平均用时统计。
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