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;
#define FOR(i, FN) for(int i = 0; i < ( FN ); i++)

int main() {
    int N;
    cin >> N;
    int d[4];
    FOR(i, 4){
        d[i] = N % 10;
        N /= 10;
    }
    int ans[3];
    FOR(op, 8){
        int hoge = op;
        FOR(i, 3){
            ans[i] = hoge & 0b001;
            hoge >>= 1;
        }
        int sum = d[3];
        for(int i = 2; i >= 0; i--) {
            if(ans[i] == 0) sum += d[i];
            else sum -= d[i];
        }
        if(sum == 7) {
            break;
        }
    }
    cout << d[3];
    FOR(i, 3){
        if(ans[2 - i] == 0) cout << "+" << d[2 - i];
        else cout << "-" << d[2 - i];
    }
    cout << "=" << 7 << endl;

    return 0;
}