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;

namespace c
{
    class Program
    {
        static void Main(string[] args)
        {
            var _ = Console.ReadLine().ToCharArray();
            var a = int.Parse(_[0].ToString());
            var b = int.Parse(_[1].ToString());
            var c = int.Parse(_[2].ToString());
            var d = int.Parse(_[3].ToString());

            var op = new string[]{"+", "-"};
            for(var i = 0; i < 2; i++){
                for(var j = 0; j < 2; j++){
                    for(var k = 0; k < 2; k++){
                        var x = Calc(a, b, op[i]);
                        var y = Calc(x, c, op[j]);                        
                        var z = Calc(y, d, op[k]);   

                        if(z == 7){
                            Console.WriteLine(
                                string.Format("{0}{1}{2}{3}{4}{5}{6}=7"
                                ,a,op[i],b,op[j],c,op[k],d));
                                return;
                        }                     
                    }
                }
            }
        }

        static int Calc(int x, int y, string op){
            if(op.Equals("+")){
                return x + y;
            }else{
                return x - y;
            }
        }
    }
}