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 <bits/stdc++.h>
using namespace std;
 
using ll = long long;
using pii = pair<int, int>;
 
template <typename T> T inf;
template <> constexpr int inf<int> = 1e9;
template <> constexpr ll inf<ll> = 1e18;

int main() {
    string a;
    cin >> a;
    string res;
    res += a[0];
    for(int S = 0; S < (1 << 3); ++S) {
        int val = a[0] - '0';
        for(int i = 0; i < 3; ++i) {
            if(S & (1 << i)) {
                val += a[i + 1] - '0';
            } else {
                val -= a[i + 1] - '0';
            }
        }
        if(val == 7) {
            for(int i = 0; i < 3; ++i) {
                res += (S & (1 << i) ? "+" : "-");
                res += a[i + 1];
            }
            break;
        }
    }
    res += "=7";
    cout << res << endl;
}