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 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		String n = sc.next();

		int A = Integer.parseInt(n.substring(0,1));
		int B = Integer.parseInt(n.substring(1,2));;
		int C = Integer.parseInt(n.substring(2,3));;
		int D = Integer.parseInt(n.substring(3,4));;

		boolean op1[] = {true,false};
		boolean op2[] = {true,false};
		boolean op3[] = {true,false};

		int cal1 = 0;
		int cal2 = 0;
		int ans = 0;

		boolean op[] = new boolean[3];

		calc:for (int i = 0; i < 2; i++) {
			if (op1[i]) {
				cal1 = A+B;
			} else {
				cal1 = A-B;
			}
			for (int j = 0; j < 2; j++) {
				if (op2[j]) {
					cal2 = cal1+C;
				} else {
					cal2 = cal1-C;
				}
				for (int k = 0; k < 2; k++) {
					if (op3[k]) {
						ans = cal2+D;
					} else {
						ans = cal2-D;
					}
					if (ans == 7) {
						op[0] = op1[i];
						op[1] = op2[j];
						op[2] = op3[k];
						break calc;
					}
				}
			}
		}
		String s[] = new String[3];
		for (int i = 0; i < 3; i++) {
			if (op[i]) {
				s[i] = "+";
			} else {
				s[i] = "-";
			}
		}
		System.out.println(A+s[0]+B+s[1]+C+s[2]+D+"=7");
	}
}