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 AtCoder {
    class Program {
        static void Main() {
            string abcd = Console.ReadLine();
            for(int b = 0; b < 1 << 3; b++) {
                int sum = abcd[0] - '0';
                string form = abcd[0].ToString();
                for(int i = 0; i < 3; i++) {
                    if((b & 1 << i) == 0) {
                        sum += abcd[i + 1] - '0';
                        form += "+" + abcd[i + 1];
                    } else {
                        sum -= abcd[i + 1] - '0';
                        form += "-" + abcd[i + 1];
                    }
                }
                if(sum == 7) {
                    Console.WriteLine($"{form}=7");
                    return;
                }
            }
        }
    }
}