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: Wrong Answer)

import java.util.Scanner

object Main extends App {
  val sc = new Scanner(System.in)
  val str = sc.next
  val a = str.substring(0,1).toInt
  val b = str.substring(1,2).toInt
  val c = str.substring(2,3).toInt
  val d = str.substring(3,4).toInt
  val abcd = Seq(a,b,c,d)
  val digits = abcd.length - 1

  for (i <- 0 until 1 << digits) {
    val sb = new StringBuilder
    sb.append(abcd(0))
    var result = abcd(0)
    for (j <- 0 until digits; n = abcd(j+1)){
      if ((i >> j & 1) == 1) {
        sb.append('+')
        result += n
      }else{
        sb.append('-')
        result -= n
      }
      sb.append(n)
    }
    if(result == 7){
      sb.append("=7")
      println(sb.toString)
    }
  }
}