Benches

IT市的城市公园由n条东西向的道路与n条南北向的道路交叉组成。因此有$n^2$个十字路口。 市政府出资购买五个长凳。为了使长凳看起来多一些，政府决定把它们们安置在尽可能多的道路上。显然，以下方案满足了这一要求：每个长凳放置在路径交叉处，并且每条道路上不放置超过一条长凳。 请你帮助公园管理局统计放置长凳的方式

The city park of IT City contains $ n $ east to west paths and $ n $ north to south paths. Each east to west path crosses each north to south path, so there are $ n^{2} $ intersections. The city funded purchase of five benches. To make it seems that there are many benches it was decided to place them on as many paths as possible. Obviously this requirement is satisfied by the following scheme: each bench is placed on a cross of paths and each path contains not more than one bench. Help the park administration count the number of ways to place the benches.

The only line of the input contains one integer $ n $ ( $ 5<=n<=100 $ ) — the number of east to west paths and north to south paths.

Output one integer — the number of ways to place the benches.

5

120