Preparando MOJI
You are given an array $$$c = [c_1, c_2, \dots, c_m]$$$. An array $$$a = [a_1, a_2, \dots, a_n]$$$ is constructed in such a way that it consists of integers $$$1, 2, \dots, m$$$, and for each $$$i \in [1,m]$$$, there are exactly $$$c_i$$$ occurrences of integer $$$i$$$ in $$$a$$$. So, the number of elements in $$$a$$$ is exactly $$$\sum\limits_{i=1}^{m} c_i$$$.
Let's define for such array $$$a$$$ the value $$$f(a)$$$ as $$$$$$f(a) = \sum_{\substack{1 \le i < j \le n\\ a_i = a_j}}{j - i}.$$$$$$
In other words, $$$f(a)$$$ is the total sum of distances between all pairs of equal elements.
Your task is to calculate the maximum possible value of $$$f(a)$$$ and the number of arrays yielding the maximum possible value of $$$f(a)$$$. Two arrays are considered different, if elements at some position differ.
The first line contains a single integer $$$m$$$ ($$$1 \le m \le 5 \cdot 10^5$$$) — the size of the array $$$c$$$.
The second line contains $$$m$$$ integers $$$c_1, c_2, \dots, c_m$$$ ($$$1 \le c_i \le 10^6$$$) — the array $$$c$$$.
Print two integers — the maximum possible value of $$$f(a)$$$ and the number of arrays $$$a$$$ with such value. Since both answers may be too large, print them modulo $$$10^9 + 7$$$.
6 1 1 1 1 1 1
0 720
1 1000000
499833345 1
7 123 451 234 512 345 123 451
339854850 882811119
In the first example, all possible arrays $$$a$$$ are permutations of $$$[1, 2, 3, 4, 5, 6]$$$. Since each array $$$a$$$ will have $$$f(a) = 0$$$, so maximum value is $$$f(a) = 0$$$ and there are $$$6! = 720$$$ such arrays.
In the second example, the only possible array consists of $$$10^6$$$ ones and its $$$f(a) = \sum\limits_{1 \le i < j \le 10^6}{j - i} = 166\,666\,666\,666\,500\,000$$$ and $$$166\,666\,666\,666\,500\,000 \bmod{10^9 + 7} = 499\,833\,345$$$.