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>
#define rep(i,n) for(long long i=0;i<(n);i++)
#define ll long long
using namespace std;
int main(){
    string s,ans;
    cin >> s;
    ans += s[0];
    int right = 7;
    for(int i=0; i<(1 << 3); i++){
        int sum = s[0] - '0';
        string op;
        for(int j = 0; j<3; j++){
            if(i & (1 << j)) op += '+';
            else op += '-';
        }
        rep(k,3){
            if(op[k] == '+') sum += s[k+1] - '0';
            else sum -= s[k+1] - '0'; 
        }
        if(sum == right){
            rep(l,3){
                ans += op[l];
                ans += s[l+1];
            }
            ans += "=7";
            break;
        }
    }
    cout << ans << endl;    
    return 0;
}