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;


namespace TestApp
{
    class Program
    {
        static void Main(string[] args)
        {
            var lists = Console.ReadLine()
                .ToArray();
            var unko = new List<KeyValuePair<string, int>>();
            
            unko.Add(new KeyValuePair<string, int>(lists[0].ToString(), int.Parse(lists[0].ToString())));
            for (int i = 1; i < 4; i++)
            {
                unko = Unkoman(unko, int.Parse(lists[i].ToString()));
            }
            foreach (var item in unko)
            {
                if(item.Value == 7)
                {
                    Console.WriteLine(item.Key +"=7");
                    break;
                }
            }
            Console.ReadLine();
        }

        static List<KeyValuePair<string,int>> Unkoman(List<KeyValuePair<string, int>> vs, int unko)
        {
            var ls = new List<KeyValuePair<string, int>>();
            foreach (var item in vs)
            {
                var key = new KeyValuePair<string, int>(item.Key + "+" + unko,item.Value + unko);
                var key2 = new KeyValuePair<string, int>(item.Key + "-" + unko, item.Value - unko);
                ls.Add(key);
                ls.Add(key2);
            }
            return ls;
        }
    }
    
}