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)

// 2020.4.16

#include <iostream>
#include <string>
#include <sstream>
#include <algorithm>
#include <numeric>
#include <stdlib.h>
#include <cstdio>

using namespace std;

char S[4];
int S2[4];
int n = 4;

int dfs(int i, int sum, string str) {
    return 0;
}

int main() {
    // cin >> S;

    // for (int i = 0; i < n; i++) {
    //     // cout << i << "番目： " << atoi(S.substr(i, 1)) << endl;
    //     // S2[i] = (int)S[i];
    //     // cout << S2[i] << endl;
    //     // cout << S[i] - '0' << endl;
    //     S2[i] = S[i] - '0';
    // }

    // dfs(1, 0, S[0]);

    scanf("%s", S);
    int a = S[0] - '0';
    int b = S[1] - '0';
    int c = S[2] - '0';
    int d = S[3] - '0';

    if (a + b + c + d == 7) printf("%d+%d+%d+%d=7\n", a, b, c, d);
    else if (a + b + c - d == 7) printf("%d+%d+%d-%d=7\n", a, b, c, d);
    else if (a + b - c + d == 7) printf("%d+%d-%d+%d=7\n", a, b, c, d);
    else if (a + b - c - d == 7) printf("%d+%d-%d-%d=7\n", a, b, c, d);
    else if (a - b + c + d == 7) printf("%d-%d+%d+%d=7\n", a, b, c, d);
    else if (a - b + c - d == 7) printf("%d-%d+%d-%d=7\n", a, b, c, d);
    else if (a - b - c + d == 7) printf("%d-%d-%d+%d=7\n", a, b, c, d);
    else if (a - b - c - d == 7) printf("%d-%d-%d-%d=7\n", a, b, c, d);
}