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 Kotlin (1.0.0) (judge verdict: Accepted)

import java.util.*

fun main(args: Array<String>) {
  val sc = Scanner(System.`in`)
  val abcd = sc.next()

  var array = BooleanArray(3) { false }

  for (bit in 0..7) {
    if (bit and 0b100 > 0) {
      array[0] = true
    }
    if (bit and 0b010 > 0) {
      array[1] = true
    }
    if (bit and 0b001 > 0) {
      array[2] = true
    }

    var tmp = Character.getNumericValue(abcd[0])
    for (i in 1..3) {
      val c = Character.getNumericValue(abcd[i])
      if (array[i - 1]) {
        tmp += c
      } else {
        tmp -= c
      }
    }
    if (tmp == 7) {
      break
    }
    array = BooleanArray(4) { false }
  }

  val ans = mutableListOf<Char>()
  ans.add(abcd[0])
  for (i in 1..3) {
    if (array[i - 1]) {
      ans.add('+')
    } else {
      ans.add('-')
    }
    ans.add(abcd[i])
  }
  println(ans.joinToString("") + "=7")


}