Tom and permutation

Time Limit: 2000/1000 MS (Java/Others)

Memory Limit: 65536/65536 K (Java/Others)

Description

Tom has learned how to calculate the number of inversions in a permutation of n distinct objects by coding, his teacher gives him a problem:
Give you a permutation of n distinct integer from 1 to n, there are many permutations of 1-n is smaller than the given permutation on dictionary order, and for each of them, you can calculate the number of inversions by coding. You need to find out sum total of them.
Tom doesn't know how to do, he wants you to help him.
Because the number may be very large, output the answer to the problem modulo ${10}^{9}+7$.

Input

Multi test cases(about 20). For each case, the first line contains a positive integer n, the second line contains n integers, it's a permutation of 1-n.
$n\leq 100$

Output

For each case, print one line, the answer to the problem modulo ${10}^{9}+7$.

Sample Input

3 2 1 3 5 2 1 4 3 5

Sample Output

1 75
Hint
The input may be very big, we might as well optimize input.

Hint

hujie

Source

BestCoder Round #40

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