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;
using System.Linq.Expressions;
using System.IO;
using System.Text;
using System.Diagnostics;

class Program
{
    static void Main()
    {
        string s = Console.ReadLine();
        string target = "";
        foreach (char p in new char[] { '+', '-'})
        {
            foreach (char q in new char[] { '+', '-' })
            {
                foreach (char r in new char[] { '+', '-' })
                {
                    target = s[0].ToString() + p.ToString() + s[1].ToString() + q.ToString() + s[2].ToString() + r.ToString() + s[3].ToString();
                    if(Calc(target) == 7)
                    {
                        Console.WriteLine(target + "=7");
                        return;
                    }
                }
            }
        }
    }

    static public int Calc(string s)
    {
        int ans = int.Parse(s[0].ToString());
        for(int i = 0; i < s.Length / 2; i++)
        {
            if(s[2 * i + 1] == '+')
            {
                ans += int.Parse(s[2 * (i + 1)].ToString());
            }
            else
            {
                ans -= int.Parse(s[2 * (i + 1)].ToString());
            }
        }
        return ans;
    }
}