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 <algorithm>
#include <vector>
#include <string>
using namespace std;
int main(){
  string str;
  int A[4];
  cin >> str;
  for(int i=0;i<4;i++) A[i] = str[i] - '0';

  for(int x=0;x<8;x++){
    int sum = A[0];
    for(int i=0;i<3;i++){
      if(x&(1<<i)) sum += A[i+1];
      else sum -= A[i+1];
    }
    if(sum==7){
      cout << A[0];
      for(int i=0;i<3;i++){
        if(x&(1<<i)){
          cout << '+';
        }else{
          cout << '-';
        }
        cout << A[i+1];
      }
      cout << '=' << 7 <<endl; 
      break;
    }
  }

  return 0;
}