output_description: Print the formula you made, including the part `=7`.
  
  Use the signs `+` and `-`.
  
  Do not print a space between a digit and a sign.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      ABCD
attempt: def nyu():
      N = list(map(str, input()))
      return N
  
  
  def check(LOP1, LOP2, LOP3):
      global flg1
      ls = N[0] + LOP1 + N[1] + LOP2 + N[2] + LOP3 + N[3]
      if flg1 == True:
          return
      elif eval(ls) == 7:
          print(N[0], LOP1, N[1], LOP2, N[2], LOP3, N[3], "=7", sep="")
          flg1 = True
          return
      elif LOP1 == "-" and LOP2 == "-" and LOP3 == "-":
          flg1 = True
          print(-1)
          return
  
      if LOP1 == "+":
          check("-", LOP2, LOP3)
      if LOP2 == "+":
          check(LOP1, "-", LOP3)
      if LOP3 == "+":
          check(LOP1, LOP2, "-")
  
  
  N = nyu()
  flg1 = False
  OP1 = "+"
  OP2 = "+"
  OP3 = "+"
  check(OP1, OP2, OP3)
  
problem_description: 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.
samples: [{"input": "1222", "output": "1+2+2+2=7\n    \n\nThis is the only valid solution.\n\n* * *"}, {"input": "0290", "output": "0-2+9+0=7\n    \n\n0 - 2 + 9 - 0 = 7 is also a valid solution.\n\n* * *"}, {"input": "3242", "output": "3+2+4-2=7"}]