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 (2.7.1) (judge verdict: Accepted)

require 'pp'
$DEBUG ? define_method(:dpp){|e|pp e} : define_method(:dpp){|e|}

# 空白区切の入力値を数値の配列で返却する
def gets_i_list()
  gets.chomp.split("").map(&:to_i)
end
nums = gets_i_list

0.upto(2**4 - 1) do |i|
  total = nums[0]
  ops = sprintf("%0*b",3,i).chars
  ops.each_with_index do |op, i|
    if op == "0"
      ops[i] = "+"
    else
      ops[i] = "-"
    end
  end

  ops.each_with_index do |op, i|
    if op == "+"
      total += nums[i+1]
    else
      total -= nums[i+1]
    end

    if total == 7
      puts [nums[0],ops[0],nums[1],ops[1],nums[2],ops[2],nums[3],"=7"].join
      exit
    end
  end
end