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 (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>

int
main(int argc, char *argv[])
{
  int n;
  scanf("%d", &n);
  
  int a[4], i = 3;
  while(i >= 0){
    a[i--] = n % 10;
    n /= 10;
  }

  int op[8][3] = {{1, 1, 1}, {1, 1, -1}, {1, -1, 1}, {1, -1, -1}, {-1, 1, 1}, {-1, 1, -1}, {-1, -1, 1}, {-1, -1, -1}};
  int out, k;

  for(int i = 0; i < 8; i++){
    out = a[0];
    for(int j = 0; j < 3; j++){
      out += op[i][j] * a[j + 1];
    }
    if(out == 7){
      k = i; break;
    }
  }

  printf("%d", a[0]);
  for(int i = 0; i < 3; i++){
    printf("%c%d", (op[k][i] == 1 ? '+' : '-'), a[i + 1]);
  }
  printf("%c%d", '=', 7);

  return 0;
}