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)

def dfs(i, f, sum):
    if i == 3:
        if sum == 7:
            # 答えは1つ出力すれば良いので =7 になれば終了
            print(f + "=7")
            exit()

    else:
        # 式 f の末尾に符号と次の数字を追加し、その分 sum に加減する
        dfs(i + 1, f + "+" + s[i + 1], sum + int(s[i + 1]))
        dfs(i + 1, f + "-" + s[i + 1], sum - int(s[i + 1]))

s = input()

dfs(0, s[0], int(s[0]))