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 ABC079C
{
    class Program
    {
        static void Main(string[] args)
        {
            string target = Console.ReadLine();
            int[] s = new int[4];
            for(int i=0;i<4;i++)
               s[i] = int.Parse(target[i].ToString());
            int ans = 100;
            for(int i=0;i < (1 << 3);i++){
                int tmp = s[0];
                for(int j = 0; j<3;j++){
                    if( (i & (1 << j)) >> j == 1){
                        tmp += s[j+1];
                    } else tmp -= s[j+1];
                }
                if(tmp == 7) { ans = i; break;}
            }
            string answer = s[0].ToString();
            for(int j = 0; j<3;j++)
               if( (ans & (1 << j)) >> j == 1){
                    answer += "+" + s[j+1].ToString();
                    } else answer += "-" + s[j+1].ToString();
            Console.WriteLine(answer+"=7");
//            Console.WriteLine(ans);
        }
    }
}