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 <cmath>
#include <vector>
using namespace std;

const int INF = pow(2, 31) - 1;
#define ll long long
#define DEBUG(x) cout << "DEBUG>" << #x << ":" << x << endl;
#define REP(i,n) for(ll i=0;i<(n);i++)
#define FOR(i,a,b) for(ll i=(a);i<=(b);i++)
ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}

int main() {
  vector<string> ki(2);
  ki[0] = "+";
  ki[1] = "-";
  int s;
  cin >> s;
  int D = s % 10;
  s /= 10;
  int C = s % 10;
  s /= 10;
  int B = s % 10;
  s /= 10;
  int A = s % 10;
  REP(i, 2) {
    REP(j, 2) {
      REP(k, 2) {
        int a = A;
        if(i == 0) {
          a += B;
        } else {
          a -= B;
        }
        if(j == 0) {
          a += C;
        } else {
          a -= C;
        }
        if(k == 0) {
          a += D;
        } else {
          a -= D;
        }
        if(a == 7) {
          cout << A << ki[i] << B << ki[j] << C << ki[k] << D << "=7" << endl;
          return 0;
        }
      }
    }
  }
  return 0;
}