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: Wrong Answer)

package main

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

func main() {
	scanner.Split(bufio.ScanBytes)
	a := getInt()
	b := getInt()
	c := getInt()
	d := getInt()

	ans := ""
	for i := 0; i < 2; i++ {
		tmp := a
		if i == 0 {
			tmp += b
		} else {
			tmp -= b
		}
		for j := 0; j < 2; j++ {
			if j == 0 {
				tmp += c
			} else {
				tmp -= c
			}
			for k := 0; k < 2; k++ {
				if k == 0 {
					tmp += d
				} else {
					tmp -= d
				}
				if tmp == 7 {
					ans = strconv.Itoa(a) + string('+'+i*2) + strconv.Itoa(b) + string('+'+j*2) + strconv.Itoa(c) + string('+'+j*2) + strconv.Itoa(d) + "=7"
				}
			}
		}
	}
	fmt.Println(ans)
}

// -----------------------------------------

var scanner = wordScanner()

func wordScanner() *bufio.Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	return sc
}

func getInt() int {
	scanner.Scan()
	i, err := strconv.Atoi(scanner.Text())
	if err != nil {
		panic(err)
	}
	return i
}

func getString() string {
	scanner.Scan()
	s := scanner.Text()
	return s
}