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 Go (1.6) (judge verdict: Accepted)

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

var sc = bufio.NewScanner(os.Stdin)

func next() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func main() {
	sc.Split(bufio.ScanWords)

	X := nextInt()

	A, B, C, D := X/1000, (X/100)%10, (X/10)%10, X%10

	for i := 0; i < 2; i++ {
		for j := 0; j < 2; j++ {
			for k := 0; k < 2; k++ {
				s := A
				res := strconv.Itoa(A)
				switch {
				case i % 2 == 0: s += B; res += "+" + strconv.Itoa(B)
				case i % 2 == 1: s -= B; res += "-" + strconv.Itoa(B)
				}
				switch {
				case j % 2 == 0: s += C; res += "+" + strconv.Itoa(C)
				case j % 2 == 1: s -= C; res += "-" + strconv.Itoa(C)
				}
				switch {
				case k % 2 == 0: s += D; res += "+" + strconv.Itoa(D)
				case k % 2 == 1: s -= D; res += "-" + strconv.Itoa(D)
				}

				if s == 7 {
					fmt.Println(res + "=7")
					return
				}
			}
		}
	}
}