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;

namespace AtCoder
{
    public class Code9
    {
        static void Main(string[] args)
        {
            string s1 = Console.ReadLine();

            Console.WriteLine(funcMain(s1));

            Console.ReadKey();
        }

        static public string funcMain(string arg1)
        {
            // 8パターンごとき力業で解けばよいと思う
            var i = new int[4];
            i[0] = int.Parse(arg1[0].ToString());
            i[1] = int.Parse(arg1[1].ToString());
            i[2] = int.Parse(arg1[2].ToString());
            i[3] = int.Parse(arg1[3].ToString());

            string op="";

            for (var j = 0; j < 8; j++)
            {
                op = "";
                switch (j)
                {
                    case 0:
                        op = "+++";
                        break;
                    case 1:
                        op = "++-";
                        break;
                    case 2:
                        op = "+-+";
                        break;
                    case 3:
                        op = "-++";
                        break;
                    case 4:
                        op = "+--";
                        break;
                    case 5:
                        op = "-+-";
                        break;
                    case 6:
                        op = "--+";
                        break;
                    case 7:
                        op = "---";
                        break;
                    default:break;

                }

                int i2 = i[0];
                for (var k = 0; k < op.Length; k++)
                {
                    switch (op[k])
                    {
                        case '+':
                            i2 +=i[k+1];
                            break;
                        case '-':
                            i2 -= i[k+1];
                            break;
                        default: break;
                    }

                }
                if (i2 == 7)
                    break;
            }

            return string.Format("{0}{1}{2}{3}{4}{5}{6}=7", i[0], op[0], i[1], op[1], i[2], op[2], i[3]);
        }

    }
}