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: Runtime Error)

using System;
using System.Collections.Generic;
using System.Linq;

    class Program
    {
        static void Main(string[] args)
        {
            var input = Console.ReadLine();
            var strABCD = input.Select(c=>c.ToString()).ToList();

            var opList = new List<List<string>>()
            {
                new List<string>(){ "+", "+", "+" },
                new List<string>(){ "+", "+", "-" },
                new List<string>(){ "+", "-", "+" },
                new List<string>(){ "+", "-", "-" },
                new List<string>(){ "-", "+", "+" },
                new List<string>(){ "-", "+", "-" },
                new List<string>(){ "-", "-", "+" },
                new List<string>(){ "-", "-", "-" },
            };

            Type t = Type.GetTypeFromProgID("MSScriptControl.ScriptControl");
            object obj = Activator.CreateInstance(t);
            t.InvokeMember("Language",
                System.Reflection.BindingFlags.SetProperty,
                null,
                obj,
                new object[] { "vbscript" });

            foreach (var item in opList)
            {
                var tmpAnswer = strABCD[0] + item[0] + strABCD[1] + item[1] + strABCD[2] + item[2] + strABCD[3];
                var result = t.InvokeMember("Eval",
                    System.Reflection.BindingFlags.InvokeMethod,
                    null,
                    obj,
                    new object[] { tmpAnswer });
                if (int.Parse(result.ToString()) != 7) continue;
                Console.WriteLine(tmpAnswer + "=7");
                return;
            }

        }
    }