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++ (GCC 9.2.1) (judge verdict: Accepted)

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

int main() {
    string S;
    cin >> S;
    int a = S.at(0)-'0';
    int b = S.at(1)-'0';
    int c = S.at(2)-'0';
    int d = S.at(3)-'0';
    if (a+b+c+d==7) printf("%d%c%d%c%d%c%d=7", a,'+',b,'+',c,'+',d);
    else if (a+b+c-d==7) printf("%d%c%d%c%d%c%d=7", a,'+',b,'+',c,'-',d);
    else if (a+b-c+d==7) printf("%d%c%d%c%d%c%d=7", a,'+',b,'-',c,'+',d);
    else if (a+b-c-d==7) printf("%d%c%d%c%d%c%d=7", a,'+',b,'-',c,'-',d);
    else if (a-b+c+d==7) printf("%d%c%d%c%d%c%d=7", a,'-',b,'+',c,'+',d);
    else if (a-b+c-d==7) printf("%d%c%d%c%d%c%d=7", a,'-',b,'+',c,'-',d);
    else if (a-b-c+d==7) printf("%d%c%d%c%d%c%d=7", a,'-',b,'-',c,'+',d);
    else if (a-b-c-d==7) printf("%d%c%d%c%d%c%d=7", a,'-',b,'-',c,'-',d);
}