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 <bits/stdc++.h>
using namespace std;
 
int main() {
  vector<int> v1;
  string a;
  cin >> a;
  for(int k = 0; k < 4; k++){
      int b;
      b = a.at(k) - '0';
      v1.push_back(b);
  }
  vector<char> v2(3);
  for(int i = 0; i < (1 << 3); i++){
      int p = v1.at(0);
      for(int t = 0; t < 3; t++){
          if(i & (1 << t)){
             p += v1.at(t+1);
             v2[t] = '+';
          }else{
             p -= v1.at(t+1);
             v2[t] = '-';
          }
     } 
     if(p == 7) goto end;
  }
  end:
    cout << v1.at(0) << v2.at(0) << v1.at(1) << v2.at(1) << v1.at(2) << v2.at(2) << v1.at(3) << "=7" << endl;
}