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 Scala (2.11.7) (judge verdict: Accepted)

object Main extends App {
  import scala.util.control.Breaks._
  val nums = io.StdIn.readLine().toCharArray.map(_-48)
  breakable {
    for (bit <- 0 until 1 << 3) {
      var acc = nums(0)
      val builder = StringBuilder.newBuilder
      builder.append(nums(0))
      for (i <- 0 to 2; n = nums(i+1)) {
        if ((bit >> i & 1) == 0) {builder.append('+'); acc = acc + n}
        else {builder.append('-'); acc = acc - n}
        builder.append(n)
      }
      if (acc == 7) {println(builder.toString() + "=7"); break}
    }
  }
}