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 Python (3.4.3) (judge verdict: Accepted)

def resolve():
  x = input()
  a = int(x[0])
  b = int(x[1])
  c = int(x[2])
  d = int(x[3])
  for i in range(2):
    ans1 = str(a)
    sum1 = a
    if i == 0:
      sum1 -= b
      ans1 += "-" + str(b)
    else:
      sum1 += b
      ans1 += "+" + str(b)
    for j in range(2):
      ans2 = ans1
      sum2 = sum1
      if j == 0:
        sum2 -= c
        ans2 += '-' + str(c)
      else:
        sum2 += c
        ans2 += '+' + str(c)
      for k in range(2):
        sum3 = sum2
        ans3 = ans2
        if k == 0:
          sum3 -= d
          ans3 += '-' + str(d)
        else:
          sum3 += d
          ans3 += '+' + str(d)
        if sum3 == 7:
          print(ans3 + "=7")
          return
  return

if __name__ == "__main__":
  resolve()