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)

import scala.io.StdIn

object Main extends App {

  val Array(a,b,c,d) = StdIn.readLine.toCharArray.map(_.toString.toInt)

  val ans = {
    val sign = Array("+","-")
    var ret = Array(0, 0, 0)
    for {
      i <- 0 to 1
      j <- 0 to 1
      k <- 0 to 1
    } {
      val x = if(i == 0) a + b else a - b
      val y = if(j == 0) x + c else x - c
      val z = if(k == 0) y + d else y - d
      if(z == 7) ret = Array(i, j, k)
    }
    (sign(ret(0)), sign(ret(1)), sign(ret(2)))
  }

  println(a + ans._1 + b + ans._2 + c + ans._3 + d + "=7")
}