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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String abcd = scanner.next();

        char[] split = abcd.toCharArray();
        int[] ints = new int[split.length];
        for (int i = 0; i < split.length; i++) {
            ints[i] = Character.getNumericValue(split[i]);
        }
        int digit = ints.length;

        for (int i = 0; i < Math.pow(2, digit - 1); i++) {
            int sum = 0;
            boolean sign = true; // true: +, false: -
            StringBuilder sb = new StringBuilder();
            for (int j = 0; j < digit; j++) {
                sb.append(ints[j]);
                if (sign) sum += ints[j];
                else sum -= ints[j];
                if ((1 & i >> j) == 1) {
                    sb.append("+");
                    sign = true;
                } else if (j < digit - 1) {
                    sb.append("-");
                    sign = false;
                }
            }
            if (sum == 7) {
                sb.append("=").append(sum);
                System.out.println(sb.toString());
                break;
            }
        }
    }
}