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: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;

#define int long long

signed main() {
    string s;
    cin >> s;
    vector<int> v;
    for(int i=0; i<s.size(); ++i) v.push_back(s[i]-'0');
    string ans = "";
    int f = 0;
    for(int i=0; i<2; ++i) {
        if(f) break;
        int t = v[0];
        ans = "";
        if(i==0) {t += v[1]; ans += "+";}
        else {t -= v[1]; ans += "-";}
        for(int j=0; j<2; ++j) {
            if(f) break;
            if(j==1) ans.pop_back();
            if(j==0) {t += v[2];ans+="+";}
            else {t -= v[2];ans+="-";}
            for(int k=0; k<2; ++k) {
                if(k==0) {t += v[3];ans+="+";}
                else {t -= v[3];ans+="-";}
                //cout << ans << " " << t << endl;
                if(t==7) {
                    f++;
                    break;
                }
                ans.pop_back();
            }
        }
    }
    cout << v[0] << ans[0] << v[1] << ans[1] << v[2] << ans[2] << v[3] << "=7" << endl;
    return 0;
}