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 C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <vector>

using namespace std;

vector<int> split(string &s) {
  vector<int> a(4);
  for (int i = 0; i < 4; i++) {
    a[i] = atoi(s.substr(i,1).c_str());
  }
  return a;
}

int main () {
  string s;
  cin >> s;
  vector<int> a(4);
  a = split(s);
  
  for (int bit = 0; bit < (1<<3); bit++) {
    vector<int> v;
    for (int i = 0; i < 4; i++) {
      if (bit & (1<<i)) {
        v.push_back(i);
      }
    }
    
    vector<int> cv;
    cv = split(s);
    
    for (int i = 0; i < (int)v.size(); i++) {
      cv[v[i]+1] *= -1;
    }
    
    if (cv[0] + cv[1] + cv[2] + cv[3] == 7) {
      printf("%d%+d%+d%+d=7\n", cv[0], cv[1], cv[2], cv[3]);
      return 0;
    }

  }
  
}