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 Rust (1.42.0) (judge verdict: Wrong Answer)

// -*- coding:utf-8-unix -*-

use proconio::input;

fn main() {
    input! {
        abcd: String,
    }

    let vch: Vec<i16> = abcd.chars().map(|c| c.to_digit(10).unwrap() as i16).collect();
    let vb = vec![vch[1], -vch[1]];
    let vc = vec![vch[2], -vch[2]];
    let vd = vec![vch[3], -vch[3]];
    for b in &vb {
        for c in &vc {
            for d in &vd {
                if vch[0] + b + c + d == 7 {
                    println!("{}{:+}{:+}{:+}=7", vch[0], b, c, d);
                }
            }
        }
    }
}