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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;

class Program
{
 static void Main(string[] args)
 {
   string str = Console.ReadLine();
   int[] nums = new int[4];
   int cnt = 0;
   int sum = 0;
   
   for( cnt = 0; cnt < 4; cnt++ )
   {
     nums[cnt] = int.Parse(str[cnt].ToString());
   }
   
   for( cnt = 0; cnt < 8; cnt++ )
   {
     sum = ( ( ( cnt & 0x04 ) == 0x00 ) ? nums[0] + nums[1] : nums[0] - nums[1] );
     sum = ( ( ( cnt & 0x02 ) == 0x00 ) ? sum + nums[2]: sum - nums[2] );
     sum = ( ( ( cnt & 0x01 ) == 0x00 ) ? sum + nums[3]: sum - nums[3] );
     
     if( sum == 7 )
     {
       break;
     }
   }
   
   Console.WriteLine("{0}{1}{2}{3}{4}{5}{6}=7",
                     nums[0],
                     ( ( ( cnt & 0x04 ) == 0x00 ) ? "+": "-" ),
                     nums[1],
                     ( ( ( cnt & 0x02 ) == 0x00 ) ? "+": "-" ),
                     nums[2],
                     ( ( ( cnt & 0x01 ) == 0x00 ) ? "+": "-" ),
                     nums[3]
                    );
 }
}