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.Linq;
using System.Collections.Generic;

namespace Algorithm
{
    class Program
    {
        const int ShopCount = 10;
        static void Main(string[] args)
        {
            var S = Console.ReadLine();
            var array = new int[S.Length];
            for (var i = 0; i < S.Length; i++)
                array[i] = int.Parse(S[i].ToString());

            var ope = "";
            for (var bit = 0; bit < (1 << array.Length); bit++)
            {
                var total = 0;
                for (var i = 0; i < array.Length; i++)
                {
                    if (i == 0)
                        total += array[i];
                    else
                    {
                        if ((bit & (1 << i)) != 0)
                        {
                            total += array[i];
                            ope += "+";
                        }
                        else
                        {
                            total -= array[i];
                            ope += "-";
                        }
                    }
                }
                if (total == 7)
                    break;
                ope = "";
            }

            Console.WriteLine($"{array[0]}{ope[0]}{array[1]}{ope[1]}{array[2]}{ope[2]}{array[3]}=7");
        }
    }
}