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);
        char[] s = sc.next().toCharArray();
        int[] a = new int[4];
        for(int i=0;i<4;i++){
            a[i] = s[i]-'0';
        }
        sc.close();
        int sum;
        int sign = 1;
        for(int i=0;i<8;i++){
            sign = 1;
            sum = 0;
            for(int j=0;j<3;j++){
                if(((i>>2-j)&1)==1){
                    sum+=sign*a[j];
                    sign = 1;
                }else{
                    sum+=sign*a[j];
                    sign = -1;
                }
            }
            sum+=a[3]*sign;
            if(sum==7){
                StringBuilder sb = new StringBuilder();
                for(int j=0;j<3;j++){
                    sb.append(a[j]);
                    if(((i>>2-j)&1)==1){
                        sb.append('+');
                    }else{
                        sb.append('-');
                    }
                }
                sb.append(a[3]);
                sb.append("=7");
                System.out.println(sb.toString());
                return;
            }
        }
    }

}