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();
   
   for(int mask = 0;mask < (1 << n - 1);++mask){
     int t = s[0] - '0';
     char c[3];
     for(int i = 0;i < n - 1;++i){
       if(mask & (1 << i)){
         t += s[i + 1] - '0';
         c[i] = '+';
       }else{
         t -= s[i + 1] - '0';
         c[i] = '-';
       }
     }
     if(t == 7){
       for(int j = 0; j < n - 1;++j){
         cout << s[j] << c[j];
       }
       cout << s[n - 1] << "=7" <<endl;
       break;
     }
   }
   return 0;
 }