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 <iostream>
using namespace std;
int main(){
  int A[4];
  char c;
  for(int i=0;i<4;i++){
    cin >> c;A[i]=c-'0';
  }
  for(int bf=0;bf < (1<<3);bf++){
    int sum=A[0]+A[1]+A[2]+A[3];
    for(int k=1;k<4;k++){
      if(bf & (1<<k))sum-=2*A[k];
    }
    if(sum==7){
      cout << A[0];
      for(int k=1;k<4;k++){
      	if(bf & (1<<k))cout << '-';
        else cout << '+';
        cout << A[k];
      }
      cout << "=7" << endl;
      return 0;
    }
  }
  return 0;
}