Problem:
Score : 300 points

Problem Statement

You are given a string S consisting of digits between 1 and 9, inclusive.
You can insert the letter + into some of the positions (possibly none) between two letters in this string.
Here, + must not occur consecutively after insertion.

All strings that can be obtained in this way can be evaluated as formulas.

Evaluate all possible formulas, and print the sum of the results.

Constraints

1 \leq |S| \leq 10

All letters in S are digits between 1 and 9, inclusive.

Input

The input is given from Standard Input in the following format:

S

Output

Print the sum of the evaluated value over all possible formulas.

Sample Input 1

125

Sample Output 1

176

There are 4 formulas that can be obtained: 125, 1+25, 12+5 and 1+2+5. When each formula is evaluated,

125

1+25=26

12+5=17

1+2+5=8

Thus, the sum is 125+26+17+8=176.

Sample Input 2

9999999999

Sample Output 2

12656242944

Solution in Ruby (2.3.3) (judge verdict: Accepted)

# 愚直にやる以外の方法がまっっっっったく浮かばないのだが？？？
# いくつ入れるか+どこにいれるか

# 実装が頭ハゲるかと思った...1時間くらいかかったのでは...

s = gets.chomp.chars.map(&:to_i)
ans = s.map(&:to_s).join.to_i
def perm(i, current_arr, source_arr, limit)
  length = source_arr.size
  # return  if length < limit
  if current_arr.size == limit
    @res_arr << current_arr
  else
    i.upto(length) do |j|
      next if i==j
      perm(j, current_arr.clone<<source_arr[j-1], source_arr, limit)
    end
  end
end

def s(arr, s)
  ai = 0
  ret = 0
  cur = 0
  s.each.with_index do |sv, sidx|
    if ai < arr.size && sidx==arr[ai]
      ret += cur*10+sv
      cur = 0
      ai+=1
      next
    end
    cur *=10
    cur += sv
  end
  ret += cur
  return ret
end

# 入れる場所は0からs.size-1箇所
1.upto(s.size-1) do |i|
  @res_arr = []
  perm(0, [], (0...s.size-1).to_a, i)
  @res_arr.each do |a|
    ans+=s(a, s)
  end
end
p ans