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;

namespace AtCoder
{
    class Program
    {
        private const int MODULO = 1000000007;
        private static string Read() { return Console.ReadLine(); }
        private static int ReadInt() { return int.Parse(Read()); }
        private static long ReadLong() { return long.Parse(Read()); }
        private static double ReadDouble() { return double.Parse(Read()); }
        private static int[] ReadInts() { return Array.ConvertAll(Read().Split(), int.Parse); }
        private static long[] ReadLongs() { return Array.ConvertAll(Read().Split(), long.Parse); }
        private static double[] ReadDoubles() { return Array.ConvertAll(Read().Split(), double.Parse); }

        static string Solve(string ABCD)
        {
            var v = Enumerable.Range(0, 4).Select(i => ABCD[i] - '0').ToArray();
            for (int i = 0; i < 8; ++i)
            {
                int sum = v[0];
                var sb = new StringBuilder(ABCD.Substring(0, 1));
                for (int j = 1; j < 4; ++j)
                {
                    if ((i & (1 << (j - 1))) != 0)
                    {
                        sum -= v[j];
                        sb.Append('-');
                    }
                    else
                    {
                        sum += v[j];
                        sb.Append('+');
                    }
                    sb.Append(ABCD[j]);
                }
                sb.Append("=7");
                if (sum == 7) { return sb.ToString(); }
            }
            return "";
        }
        static void Main(string[] args)
        {
            Console.WriteLine(Solve(Read()));
        }
    }
}