Problem:
Score : 300 points

Problem Statement

Sitting in a station waiting room, Joisino is gazing at her train ticket.

The ticket is numbered with four digits A, B, C and D in this order, each between 0 and 9 (inclusive).

In the formula A op1 B op2 C op3 D = 7, replace each of the symbols op1, op2 and op3 with + or - so that the formula holds.

The given input guarantees that there is a solution. If there are multiple solutions, any of them will be accepted.

Constraints

0≤A,B,C,D≤9

All input values are integers.

It is guaranteed that there is a solution.

Input

Input is given from Standard Input in the following format:

ABCD

Output

Print the formula you made, including the part =7.

Use the signs + and -.

Do not print a space between a digit and a sign.

Sample Input 1

1222

Sample Output 1

1+2+2+2=7

This is the only valid solution.

Sample Input 2

0290

Sample Output 2

0-2+9+0=7

0 - 2 + 9 - 0 = 7 is also a valid solution.

Sample Input 3

3242

Sample Output 3

3+2+4-2=7

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

def calc(lhs, op, rhs)
  if op == '+'
    lhs + rhs
  else
    lhs - rhs
  end
end

def main
  nums = ARGF.gets.chars.map(&:to_i)
  # puts nums

  ['+', '-'].each do |op1|
    ans1 = calc(nums[0], op1, nums[1])

    ['+', '-'].each do |op2|
      ans2 = calc(ans1, op2, nums[2])

      ['+', '-'].each do |op3|
        ans3 = calc(ans2, op3, nums[3])

        if ans3 == 7
          puts "#{nums[0]}#{op1}#{nums[1]}#{op2}#{nums[2]}#{op3}#{nums[3]}=7"
          return
        end
      end
    end
  end

  puts 'error'  # 問題の前提上、ありえない
end

if __FILE__ == $0
  main
end