Title Description

Given a set $s$(number of set elements $\le 30$), calculate the sum of all subset elements in this set.

Input format

The elements in the collection (element $\le 1000$)

Output format

The sum of all subset elements.

2 3

10

Reminder

[Example Explanation]

The subsets are: $\varnothing, \{ 2 \}, \{ 3 \}, \{ 2, 3 \}$, and $2+3+2+3=10$.

[Data Range]

For data of $100 \%$, $1 \le \lvert s \rvert \le 30$, $1 \le s_i \le 1000$, $s$the sum of all subset elements $\le {10} ^ {18}$.