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 Java7 (OpenJDK 1.7.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main {

	static int a[] = new int[4];

	public static int seven(int s) {
		int ans = a[0], e = s;
		if(s >= 8)return -1;
		for (int i = 0; i < 3; ++i) {
			int tmp = 1 & e;
			if (tmp == 1)
				ans += a[i + 1];
			else
				ans -= a[i + 1];
			e = e >> 1;
		}
		if (ans == 7)
			return s;
		else
			return (seven(++s));
	}

	public static String make(int s) {
		String ans = Integer.toString(a[0]);
		int e = s;
		for (int i = 0; i < 3; ++i) {
			if ((e & 1) == 1)
				ans += "+";
			else
				ans += "-";
			e = e >> 1;
			ans += Integer.toString(a[i + 1]);
		}

		ans += "=7";
		return ans;
	}

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String in = sc.next();
		sc.close();
		for (int i = 0; i < 4; ++i) {
			a[i] = Integer.parseInt(in.substring(i,  i + 1));
		}
		int s = seven(0);
		System.out.println(make(s));

	}

}