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;
public class Hello{
    public static void Main(){
        string s = Console.ReadLine();
        
        string[] oprnd = {"---","--+","-+-","+--","++-","+-+","-++","+++"};
        int[] nums = new int[4];
        for(var n = 0;n < 4;n++){
            nums[n] = int.Parse(s[n].ToString());
        }
        var target = 7 - nums[0];
 
        for(var i = 0;i < 8;i++){
            var ans = $"{nums[0]}";
            var temp = 0;
            for(var j = 0;j < 3;j++){
                if(oprnd[i][j] == '+'){
                    temp += nums[j + 1];
                    ans += $"+{nums[j + 1]}";
                }else{
                    temp -= nums[j + 1];
                    ans += $"-{nums[j + 1]}";
                }
            }
            
            if(temp == target){
                Console.WriteLine(ans + "=7");
                return;
            }
        }
        
        
    }
}