You are given an array $$$a_1, a_2, \dots, a_n$$$. All $$$a_i$$$ are pairwise distinct.
Let's define function $$$f(l, r)$$$ as follows:
Calculate $$$\left(\sum\limits_{1 \le l \le r \le n}{f(l, r)}\right) \mod (10^9+7)$$$, i.e. total sum of $$$f$$$ for all subsegments of $$$a$$$ modulo $$$10^9+7$$$.
The first line contains one integer $$$n$$$ ($$$1 \le n \le 5 \cdot 10^5$$$) — the length of array $$$a$$$.
The second line contains $$$n$$$ integers $$$a_1, a_2, \dots, a_n$$$ ($$$1 \le a_i \le 10^9$$$, $$$a_i \neq a_j$$$ for $$$i \neq j$$$) — array $$$a$$$.
Print one integer — the total sum of $$$f$$$ for all subsegments of $$$a$$$ modulo $$$10^9+7$$$
4 5 2 4 7
167
3 123456789 214365879 987654321
582491518
Description of the first example:
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