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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
public class Program
{
    public static void Main()
    {
        int[] n = Console.ReadLine().ToCharArray().Select(num => int.Parse(num.ToString())).ToArray();
        int a, b, c;
        string a_, b_, c_;
        int box = 0;
        for (int i = 0; i < 2; i++)
        {
            if (i == 1) { a = -1 * n[1]; a_ = "-"; }
            else { a = n[1]; a_ = "+"; }
            for (int j = 0; j < 2; j++)
            {
                if (j == 1) { b = -1 * n[2]; b_ = "-"; }
                else { b = n[2]; b_ = "+"; }
                for (int k = 0; k < 2; k++)
                {
                    if (k == 1) { c = -1 * n[3]; c_ = "-"; }
                    else { c = n[3]; c_ = "+"; }
                    box = a + b + c;
                    if (box + n[0] == 7)
                    {
                        Console.WriteLine(n[0] + a_ + n[1] + b_ + n[2] + c_ + n[3] + "=7");
                        return;
                    }
                }
            }
        }
    }
}