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 <algorithm>
#include <climits>
#include <complex>
#include <cstring>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <vector>

// using
using namespace std;

// typedef
typedef long long ll;

// define
#define ALL(c) (c).begin(), (c).end()
#define SORT(c) sort(ALL(c))
#define REVERSE(c) reverse(ALL(c))
#define UNIQ(c) unique(ALL(c))
#define FOR(i, a, b, c) for (int i = (int)(a); i < (int)(b); i += (int)(c))
#define REP(i, n) FOR(i, 0, n, 1)
#define RFOR(i, a, b, c) for (int i = (int)(a); i >= (int)(b); i -= (int)(c))
#define RREP(i, n) RFOR(i, n, 0, 1)

// functions
template <class T> T ceil(T a, T b) {
    return (a + b - 1) / b;
}
template <class T> T round(T a, T b) {
    return (a + b / 2) / b;
}
template <class T> T gcd(T a, T b) {
    return b ? gcd(b, a % b) : a;
}
template <class T> T lcm(T a, T b) {
    return a * b / gcd(a, b);
}
template <class T> bool amax(T& a, const T& b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
template <class T> bool amin(T& a, const T& b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}

// main
int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    int X;
    cin >> X;
    int A[4];
    REP(i, 4) {
        A[3 - i] = X % 10;
        X /= 10;
    }
    REP(i, 1 << 3) {
        int val = A[0];
        string res = to_string(A[0]);
        REP(j, 3) {
            int a = A[j + 1];
            if ((i >> j) & 1) {
                val += a;
                res += "+" + to_string(a);
            } else {
                val -= a;
                res += "-" + to_string(a);
            }
        }
        if (val == 7) {
            cout << res + "=7" << endl;
            break;
        }
    }
    return 0;
}