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>
#define FOR(i,x,y) for(int i = x;i < y;i++)
using namespace std;

int ctoi(char c){
  string s = "0123456789";
  FOR(i,0,10)if(c == s[i])return i;
  return 0;
}

int op[] = {-1,1};

int main(){
  string S;
  cin >> S;
  int A = ctoi(S[0]);
  int B = ctoi(S[1]);
  int C = ctoi(S[2]);
  int D = ctoi(S[3]);
  FOR(i,0,2)FOR(j,0,2)FOR(k,0,2){
    if(A+op[i]*B+op[j]*C+op[k]*D == 7){
      cout << A;
      i ? cout << "+" : cout << "-";
      cout << B;
      j ? cout << "+" : cout << "-";
      cout << C;
      k ? cout << "+" : cout << "-";
      cout << D << "=7" << endl;
      i = 2;
      j = 2;
      k = 2;
    }
  }
}