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: Wrong Answer)


import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		int n = s.length();
		for(int mask = 0 ; mask < 1<<(n-1) ; mask++) {
			int sum = (int)(s.charAt(0) - '0');
			String x = "" + s.charAt(0);
			for(int i = 0 ; i < s.length() - 1 ; i++) {
				if((mask&(1<<i)) >= 1) {
					sum += (int)(s.charAt(n - 1 - i) - '0');
					x += "+" + s.charAt(i + 1);
				} else {
					sum -= (int)(s.charAt(n - 1 - i) - '0');
					x += "-" + s.charAt(i + 1);
				}
			}
			if(sum == 7) {
				System.out.println(x + "=7");
				return;
			}
		}
	}
}