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 abc079_c
{
    class Program
    {
        static void Main(string[] args)
        {
            var ABCDs = GetStr();
            var ABCD = new List<int>();
            foreach(var c in ABCDs) 
                ABCD.Add(int.Parse(c.ToString()));

            for (int i = 0; i <= 1; i++) 
                for (int j = 0; j <= 1; j++)
                    for (int k = 0; k <= 1; k++)
                    {
                        int r = ABCD[0];
                        r += i == 0 ? ABCD[1] : -1 * ABCD[1];
                        r += j == 0 ? ABCD[2] : -1 * ABCD[2];
                        r += k == 0 ? ABCD[3] : -1 * ABCD[3];
                        if (r == 7)
                        {
                            Console.WriteLine(ABCD[0] + (i == 0 ? "+" : "-") + ABCD[1] + (j == 0 ? "+" : "-") + ABCD[2] + (k == 0 ? "+" : "-") + ABCD[3] + "=7");
                            return;
                        }
                    }
        }

        public static string GetStr() => Console.ReadLine();
        public static int GetInt() => int.Parse(Console.ReadLine());
        public static long GetLong() => long.Parse(Console.ReadLine());
        public static double GetDouble() => double.Parse(Console.ReadLine());
        public static decimal GetDecimal() => decimal.Parse(Console.ReadLine());

        public static List<string> GetStrList() => Console.ReadLine().Split(' ').ToList();
        public static List<int> GetIntList() => Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToList();
        public static List<long> GetLongList() => Console.ReadLine().Split(' ').Select(x => long.Parse(x)).ToList();
        public static List<double> GetDoubleList() => Console.ReadLine().Split(' ').Select(x => double.Parse(x)).ToList();
        public static List<decimal> GetDecimalList() => Console.ReadLine().Split(' ').Select(x => decimal.Parse(x)).ToList();

    }
}