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.IO;
using System.Text.RegularExpressions;
using System.Text;
using System.Diagnostics;
using static System.Math;
using static System.Array;

//var input = Console.ReadLine().Split().Select(int.Parse).ToArray();
namespace AtCoderSolve
{

    class Solve
    {
        const int mod = 1000000007;
        const int INF = 2147483647;
        const long SINF = 9223372036854775807;

        //static int N;
        static string S;
        static int[] p;
       

        public static void Input()
        {
            var cin = new Scanner();
            S = Console.ReadLine();
            p = new int[4];
            for(var i = 0; i < 4; i++)
            {
                p[i] = S[i] - '0';
            }
        }

        static void Main(string[] args)
        {
            Input();

            //var sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
            //Console.SetOut(sw);

            for(var bit = 0; bit < (1 << 3); bit++)
            {
                int sum = p[0];
                var ans = new StringBuilder();
                ans.Append($"{p[0]}");
                for(var i = 0; i < 3; i++)
                {
                    if ((bit & (1 << i)) != 0)
                    {
                        sum += p[i + 1];
                        ans.Append($"+{p[i + 1]}");
                    }
                    else
                    {
                        sum -= p[i + 1];
                        ans.Append($"-{p[i + 1]}");
                    }
                }

                if (sum == 7)
                {
                    ans.Append("=7");
                    Console.WriteLine(ans);
                    return;
                }

            }
            

            //Console.Out.Flush();

        }

       
    }

    public class Scanner
    {
        public int[] SplitReader()
        {
            int[] array = Console.ReadLine().Split().Select(int.Parse).ToArray();
            return array;
        }
        public long[] SplitReaderL()
        {
            long[] array = Console.ReadLine().Split().Select(long.Parse).ToArray();
            return array;
        }

    }

    public class Graph
    {
        
    }
}