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 (
	"fmt"
	"strconv"
)

func main() {
	var inputLine string
	fmt.Scan(&inputLine)
	runeS := []rune(inputLine)
	var nums []int
	for _, c := range runeS {
		n, _ := strconv.Atoi(string(c))
		nums = append(nums, n)
	}

	var temp int
	var s string
	for i := 0; i < (1 << uint(len(nums)-1)); i++ {
		temp = nums[0]
		s = strconv.Itoa(nums[0])
		for j := 0; j < (len(nums) - 1); j++ {
			if (i>>uint(j))&1 == 1 {
				temp += nums[j+1]
				s += "+" + strconv.Itoa(nums[j+1])
			} else {
				temp -= nums[j+1]
				s += "-" + strconv.Itoa(nums[j+1])
			}
		}
		if temp == 7 {
			s += "=7"
			fmt.Println(s)
			break
		}
	}
}