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: Wrong Answer)

    using System;
    using System.Linq;
    using System.Collections.Generic;
    using static System.Math;

    public class Program
    {
        public static void Main(string[] args)
        {
            string input = Console.ReadLine();
            List<int> number = new List<int> { };
            int stock = 0;
            int idx = 0;
            string answer = "";

            for (int i = 0; i < input.Length; i++)
            {
                number.Add(int.Parse(input.Substring(i, 1)));
            }

            foreach (int j in number)
            {
                stock += j;
            }

            if (stock > 7)
            {
                for (int x = 0; x < number.Count(); x++)
                {
                    int y = stock;
                    if (y - 2 * number[x] == 7)
                    {
                        idx = x;
                        break;
                    }
                }
            }

            for (int n = 0; n < number.Count(); n++)
            {
                answer += number[n];
                if (n == number.Count() - 1) break;
                if (n == idx - 1) answer += "-";
                else answer += "+";
            }

            Console.WriteLine(answer + "=7");
        }
    }