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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>

using namespace std;

int Bit(int num, int pos)
{
    return (num & (1 << pos)) ? 1 : 0;
}

bool Good(const string &str, int mask)
{
    int sum = str[0] - '0';
    for (int i = 0; i < 3; i += 1) {
        sum += (str[i + 1] - '0') * (Bit(mask, i) == 1 ? 1 : -1);
    }
    return sum == 7;
}

void Print(const string &str, int mask)
{
    for (int i = 0; i < 3; i += 1) {
        cout << str[i] << (Bit(mask, i) == 1 ? '+' : '-');
    }
    cout << str.back() << "=7\n";
}

int main()
{
    string str;
    getline(cin, str);

    for (auto i = 0; i < (1 << 3); i += 1) {
        if (Good(str, i)) {
            Print(str, i);
            return 0;
        }
    }

    return 0;
}