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.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        char[] S = sc.nextLine().toCharArray();
        int n = S.length;

        for (int i = 0; i < (1 << n - 1); i++) {
            Queue<String> queue = new LinkedList<>();

            // char -> long
            long sum = (S[0] - '0');
            queue.add(String.valueOf(S[0]));
            for (int j = 0; j < n - 1; j++) {
                if ((i & (1 << j)) != 0) {
                    sum += S[j + 1] - '0';
                    queue.add("+");
                } else {
                    sum -= S[j + 1] - '0';
                    queue.add("-");
                }
                queue.add(String.valueOf(S[j + 1]));
            }

            if (sum == 7) {
                while(!queue.isEmpty()) {
                    System.out.print(queue.remove());
                }
                System.out.print("=7");
                return;
            }
        }
    }
}