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() {
   string S;
  cin >> S;
  int n = S.size() -1;
  
  string A = "";
  A += S.at(0);
  for (int i=1; i<(S.size()); i++){
    A += ' ';
    A += S.at(i);
  }
  for (int i=0; i< (1 << n); i++) {
     int ans = S.at(0) - '0';
     for (int j=0; j<n; j++) {
       if (i&(1<<j)){
       ans += S.at(j+1) - '0';
       A.at(2*(j+1)-1) = '+' ;
       }
       else{
       ans -= S.at(j+1) - '0';
       A.at(2*(j+1)-1) = '-';
       }
     }
       if (ans == 7) {
         cout << A << "=7" << endl;
         break;
       } 
  }
}