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(){
  int num;
  cin >> num;
  int a[4];
  for (int i = 3; i >= 0; i--){
    a[i] = num % 10;
    num /= 10;
  }

  if (a[0] - a[1] - a[2] - a[3] == 7) printf("%d-%d-%d-%d=7\n", a[0], a[1], a[2], a[3]);
  else if (a[0] + a[1] - a[2] - a[3] == 7) printf("%d+%d-%d-%d=7\n", a[0], a[1], a[2], a[3]);
  else if (a[0] + a[1] + a[2] - a[3] == 7) printf("%d+%d+%d-%d=7\n", a[0], a[1], a[2], a[3]);
  else if (a[0] + a[1] + a[2] + a[3] == 7) printf("%d+%d+%d+%d=7\n", a[0], a[1], a[2], a[3]);
  else if (a[0] - a[1] + a[2] - a[3] == 7) printf("%d-%d+%d-%d=7\n", a[0], a[1], a[2], a[3]);
  else if (a[0] - a[1] + a[2] + a[3] == 7) printf("%d-%d+%d+%d=7\n", a[0], a[1], a[2], a[3]);
  else if (a[0] - a[1] - a[2] + a[3] == 7) printf("%d-%d-%d+%d=7\n", a[0], a[1], a[2], a[3]);
  else if (a[0] + a[1] - a[2] + a[3] == 7) printf("%d+%d-%d+%d=7\n", a[0], a[1], a[2], a[3]);

  return 0;
}