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 Python (3.4.3) (judge verdict: Accepted)

import numpy as np

nyuryoku=input()

s=[int(i) for i in nyuryoku]

s_array=np.array(s)

if np.sum(s_array)==7:
    Ans=['+'+str(i) for i in s]
    Ans[0]=str(s[0])
    print(''.join(Ans)+'=7')
    
else:
    for i in range(3):
        if np.sum(s_array)-2*s_array[i+1]==7:
            Ans=['+'+str(i) for i in s]
            Ans[0]=str(s[0])
            Ans[i+1]='-'+str(s[i+1])
            print(''.join(Ans)+'=7')
            break
            
        elif np.sum(s_array)-2*s_array[1]-2*s_array[2]==7:
            Ans=['+'+str(i) for i in s]
            Ans[0]=str(s[0])
            Ans[1]='-'+str(s[1])
            Ans[2]='-'+str(s[2])
            print(''.join(Ans)+'=7')
            break
            
        elif np.sum(s_array)-2*s_array[2]-2*s_array[3]==7:
            Ans=['+'+str(i) for i in s]
            Ans[0]=str(s[0])
            Ans[2]='-'+str(s[2])
            Ans[3]='-'+str(s[3])
            print(''.join(Ans)+'=7')
            break
        
        elif np.sum(s_array)-2*s_array[1]-2*s_array[3]==7:
            Ans=['+'+str(i) for i in s]
            Ans[0]=str(s[0])
            Ans[1]='-'+str(s[1])
            Ans[3]='-'+str(s[3])
            print(''.join(Ans)+'=7')
            break
            
        elif np.sum(s_array)-2*s_array[1]-2*s_array[2]-2*s_array[3]==7:
            Ans=['+'+str(i) for i in s]
            Ans[0]=str(s[0])
            Ans[1]='-'+str(s[1])
            Ans[2]='-'+str(s[2])
            Ans[3]='-'+str(s[3])
            print(''.join(Ans)+'=7')
            break