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.Arrays;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		new Main().run();
	}

	void run() {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		int[] a = new int[s.length()];
		for (int i = 0; i < s.length(); ++i) {
			a[i] = (int) (s.charAt(i) - '0');
		}
		for (int i = -1; i <= 1; i += 2) {
			for (int j = -1; j <= 1; j += 2) {
				for (int k = -1; k <= 1; k += 2) {
					if (a[0] + i * a[1] + j * a[2] + k * a[3] != 7)
						continue;
					int[] v = new int[] { i, j, k };
					for (int l = 0; l < 4; ++l) {
						System.out.print(a[l]);
						if (l < 3)
							System.out.print(v[l] == 1 ? "+" : "-");
					}
					System.out.println("=7");
					return;

				}
			}
		}
	}

	void tr(Object... objects) {
		System.out.println(Arrays.deepToString(objects));
	}
}