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>
#include <string>
#include <sstream>
#include <iomanip>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <queue>
#include <cmath>
#include <stack>

using namespace std;
using ll = long long;
using lli = long long int;

void ABC079C()
{
	string str;
	cin >> str;
	vector<int> num(4);
	for (int i = 0; i < 4; ++i)
	{
		num[i] = stoi(str.substr(i, 1));
	}

	for (int i = 0; i < (1 << 3); ++i)
	{
		stringstream ss;
		int sum = num[0];
		ss << num[0];
		for (int j = 0; j < 3; ++j)
		{
			if (0 == (i & (1 << j)))
			{
				sum += num[j + 1];
				ss << '+' << num[j + 1];
			}
			else
			{
				sum -= num[j + 1];
				ss << '-' << num[j + 1];
			}
		}
		if (sum == 7)
		{
			ss << "=7" << endl;
			cout << ss.str() << endl;
			break;
		}
	}
}

int main()
{
	ABC079C();
	return 0;
}