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(arg: Array<String>) {
    val (A, B, C, D) = next().map { it - '0' }
    fun sign(a: Int) = if (a < 0) '-' else '+'
    for (bit in 0 until (1 shl 3)) {
        val b = if (((bit shr 0) and 1) == 1) -B else B
        val c = if (((bit shr 1) and 1) == 1) -C else C
        val d = if (((bit shr 2) and 1) == 1) -D else D
//System.err.println("$bit:  $A${sign(b)}$B${sign(c)}$C${sign(d)}$D=${A+b+c+d}")
        if (A + b + c + d == 7) {
            println("$A${sign(b)}$B${sign(c)}$C${sign(d)}$D=7")
            return
        }
    }
}
fun next() = readLine()!!
fun nextInt(delta: Int = 0) = Integer.parseInt(next()) + delta
fun listOfString() = next().split(" ")
fun listOfInt() = listOfString().map { Integer.parseInt(it) }
fun listOfLong() = listOfString().map(String::toLong)