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"
)

const mod = 1000000007

// 1MB
const ioBufferSize = 1 * 1024 * 1024

var sc = func() *bufio.Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Buffer(make([]byte, ioBufferSize), ioBufferSize)
	sc.Split(bufio.ScanWords)
	return sc
}()

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 abs(x int) int {
	if x < 0 {
		return -x
	}
	return x
}

func main() {
	n := nextInt()
	a, b, c, d := n/1000, (n/100)%10, (n/10)%10, n%10

	if a+b+c+d == 7 {
		fmt.Printf("%d+%d+%d+%d=7\n", a, b, c, d)
	} else if a+b+c-d == 7 {
		fmt.Printf("%d+%d+%d-%d=7\n", a, b, c, d)
	} else if a+b-c+d == 7 {
		fmt.Printf("%d+%d-%d+%d=7\n", a, b, c, d)
	} else if a+b-c-d == 7 {
		fmt.Printf("%d+%d-%d-%d=7\n", a, b, c, d)
	} else if a-b+c+d == 7 {
		fmt.Printf("%d-%d+%d+%d=7\n", a, b, c, d)
	} else if a-b+c-d == 7 {
		fmt.Printf("%d-%d+%d-%d=7\n", a, b, c, d)
	} else if a-b-c+d == 7 {
		fmt.Printf("%d-%d-%d+%d=7\n", a, b, c, d)
	} else if a-b-c-d == 7 {
		fmt.Printf("%d-%d-%d-%d=7\n", a, b, c, d)
	}
}