P9316 [AtCoder] AtCoder Beginner Contest 150 - Change a Little Bit
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题目描述

For two sequences S and T of length N consisting of 0 and 1, let us define f(S, T) as follows:

  • Consider repeating the following operation on S so that S will be equal to T. f(S, T) is the minimum possible total cost of those operations.

  • Change S_i (from 0 to 1 or vice versa). The cost of this operation is $D \times C_i$, where D is the number of integers j such that $S_j \neq T_j (1 \leq j \leq N)$ just before this change.

There are $2^N \times (2^N - 1) pairs (S, T)$ of different sequences of length N consisting of 0 and 1. Compute the sum of f(S, T) over all of those pairs, modulo (10^9+7).

Constraints

  • $1 \leq N \leq 2 \times 10^5$
  • $1 \leq C_i \leq 10^9$
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
$C_1 C_2 \cdots C_N$

Output

Print the sum of f(S, T), modulo (10^9+7).

Examples

Input

1
1000000000

Output

999999993

Input

2
5 8

Output

124

Input

5
52 67 72 25 79

Output

269312

输入格式

见题面

输出格式

见题面

样例输入
2 5 8
样例输出
124