#C5197. Beautiful Arrangements
Beautiful Arrangements
Beautiful Arrangements
Given an integer (N) representing the length of a garden, determine the number of beautiful arrangements of flowers. A beautiful arrangement is defined as follows:
- For (N = 1), no arrangement is possible (the answer is 0).
- For (N = 2), there are exactly 2 arrangements.
- For (N \ge 3), the number of beautiful arrangements is given by the formula:
[ A(N)=\prod_{i=2}^{N} i \mod (10^9+7), ]
You are required to compute (A(N)) and output the result.
inputFormat
The input consists of a single integer (N) (where (1 \leq N \leq 10^6)) representing the garden length.
outputFormat
Output a single integer, the number of beautiful arrangements modulo (10^9+7).## sample
1
0
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