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 Go (1.6) (judge verdict: Accepted)

package main
 
import (
  "fmt"
  "strconv"
)

func pow (n int, r int) int {
  
  x := 1
  for i := 0; i < r; i++ {
    x *= n
  }
  return x
}

func main() {
  
  //入力値を分割
  var str string
  fmt.Scan(&str)
  var m [4]int
  for i := 0; i < 4; i++ {
    m[i],_ = strconv.Atoi(string(str[i]))
  }
  
  //+,-を格納
  var s [3]string
  
  //全パターン試して正解を見つけたら終了
  for i := 0; i < pow(2,3); i++ {
    ans := m[0]
    for j := 0; j < 3; j++ {
    //p := i & (1<<(uint(j))) 
      p :=  (i>>(uint(j))) & 1 
      if p == 0 {
        s[j] = "-"
        ans -= m[j+1]
      } else {
        s[j] = "+"
        ans += m[j+1]
      }
    }
    if ans == 7 { 
      fmt.Printf("%d%s%d%s%d%s%d=7", m[0], s[0], m[1], s[1], m[2], s[2], m[3])
      break
    }
  }
}