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 Kotlin (1.0.0) (judge verdict: Accepted)

fun main(args: Array<String>) {
    val (a, b, c, d) = readLine()!!.split("")
            .filter { it.isNotEmpty() }.map(String::toInt)
    val opList = mutableListOf<List<Int>>()
    (0..7).forEach { i ->
        run {
            opList.add(String.format("%03d", Integer.toBinaryString(i).toInt()).split("").filter { it.isNotEmpty() }.map(String::toInt))
        }
    }
    for (op in opList) {
        var result = a
        result += if (op[0] == 0) b else -b
        result += if (op[1] == 0) c else -c
        result += if (op[2] == 0) d else -d
        if (result == 7) {
            val builder = StringBuilder()
            builder.append(a)
            builder.append(if (op[0] == 0) "+" else "-")
            builder.append(b)
            builder.append(if (op[1] == 0) "+" else "-")
            builder.append(c)
            builder.append(if (op[2] == 0) "+" else "-")
            builder.append(d)
            builder.append("=7")
            println(builder.toString())
            return
        }
    }
}