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: Wrong Answer)

#include <bits/stdc++.h>
#define rep(i, a, b) for(int i = a; i < b; i++)
#define _GLIBCXX_DEBUG
#define V vector<ll>
using namespace std;
using ll = long long;


int main(){
   string S; cin >> S;
   vector<int> N(4);
   rep(i, 0, 4) N[i] = S[i] - '0';
   reverse(N.begin(),N.end());

   for(int tmp = 0; tmp < 1 << 3; tmp++){
      bitset<3> s(tmp);
      int sum = 0;
      rep(i, 0, 3){
         if(s.test(i)){
            sum += N[i];
         }else{
            sum -= N[i];
         }
      }
      sum += N[3];
      if(sum == 7){
         cout << S[0];
         rep(i, 0, 3){
            cout << (s.test(i) ? '+' : '-') << S[i+1];
         }
         cout << "=7" << endl;
         return 0;
      }
   }
}