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)

val PLUS = 0
val MINUS = 1

fun main(args: Array<String>) {
    val (A, B, C, D) = readLine()!!.map { it.toInt() - 48 }
    (0..1).forEach { op1 ->
        (0..1).forEach { op2 ->
            (0..1).forEach { op3 ->
                // A, B
                if (operate(operate(operate(A, B, op1), C, op2), D, op3) == 7) {
                    println(A.toString() + stringifyOperator(op1) + B.toString() + stringifyOperator(op2) + C.toString() + stringifyOperator(op3) + D.toString() + "=7")
                    return
                }
            }
        }
    }
}


fun operate(x: Int, y: Int, operator: Int) : Int {
    if (operator == PLUS) {
        return x + y
    } else {
        return x - y
    }
}

fun stringifyOperator(num: Int) : String {
    if (num == PLUS) {
        return "+"
    } else {
        return "-"
    }
}