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.Text;
using System.Threading.Tasks;

public static class Program
{
    public static void Main(params string[] args)
    {
        var l = Console.ReadLine()
           .Select(x => int.Parse(x.ToString()))
           .ToArray();
        var op = new[] { true, false };
        foreach (var p1 in op)
        {
            foreach (var p2 in op)
            {
                foreach (var p3 in op)
                {
                    if (l[0] + (p1 ? 1 : -1) * l[1] + (p2 ? 1 : -1) * l[2] + (p3 ? 1 : -1) * l[3] == 7)
                    {
                        Console.Write(l[0]);
                        Console.Write(p1 ? "+" : "-");
                        Console.Write(l[1]);
                        Console.Write(p2 ? "+" : "-");
                        Console.Write(l[2]);
                        Console.Write(p3 ? "+" : "-");
                        Console.Write(l[3]);
                        Console.WriteLine("=7");
                        return;
                    }
                }
            }
        }
    }
}