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 (3.8.2) (judge verdict: Accepted)

def main(A,B,C,D):
    list = [A,B,C,D]

    tmp = ['+','-']


    for i in range(2**3):
        ans = A
        back = []
        for j in range(3):
            if ( (i>>j)&1 ):
                ans += list[j+1]
                back.append(tmp[0])
            else:
                ans -= list[j+1]
                back.append(tmp[1])
        if ans == 7:
            return back

tmp = int(input())
D = tmp%10
tmp = tmp//10
C = tmp%10
tmp = tmp//10
B = tmp%10
tmp = tmp//10
A = tmp%10
back = main(A,B,C,D)
print(str(A)+back[0]+str(B)+back[1]+str(C)+back[2]+str(D)+'=7')