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{
	static char get(char c) {
		if ((c - '0') == 0)
			return '-';
		return '+';
	}

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		char m[] = sc.next().toCharArray();
		int n1 = m[0] - '0';
		int n2 = m[1] - '0';
		int n3 = m[2] - '0';
		int n4 = m[3] - '0';
		for (int i = 0; i < (1 << 3); i++) {
			char[] k = Integer.toBinaryString(8 + i).toCharArray();
			//System.out.println(k);
			int ans = 0;
			ans = (k[1] - '0' == 1) ? n1 + n2 : n1 - n2;

			ans = (k[2] - '0' == 1) ? ans + n3 : ans - n3;

			ans = (k[3] - '0' == 1) ? ans + n4 : ans - n4;
			if (ans == 7) {
				System.out.println(n1 + "" + get(k[1]) + n2 + get(k[2]) + n3 + get(k[3]) + n4 + "=7");
				return;
			}

		}
	}

}