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 5.4.1) (judge verdict: Accepted)

#include<stdio.h>

int Add(int a, int b){
    return a + b;
}

int Sub(int a, int b){
    return a - b;
}

int main(){
    int N, ans[4], count = 0, all = 0;
    scanf("%4d", &N);
    ans[3] = N % 10;
    ans[2] = (N / 10) % 10;
    ans[1] = (N / 100) % 10;
    ans[0] = (N / 1000) % 10;
    for(int i = 0; i < 8; i++){
        all = ans[0];
        for(int j = 0; j < 3; j++){
            if(j > 0){
                if((i / (j * 2)) % 2 == 0){
                    all = Add(all, ans[j + 1]);
                }else{
                    all = Sub(all, ans[j + 1]);
                }
            }else{
                if(i % 2 == 0){
                    all = Add(all, ans[j + 1]);
                }else{
                    all = Sub(all, ans[j + 1]);
                }
            }
        }
        if(all == 7){
            for(int j = 0; j < 3; j++){
                printf("%d", ans[j]);
                if(j > 0){
                    if((i / (j * 2)) % 2 == 0){
                        printf("+");
                    }else{
                        printf("-");
                    }
                }else{
                    if(i % 2 == 0){
                        printf("+");
                    }else{
                        printf("-");
                    }
                }
            }
            printf("%d=7\n", ans[3]);
            break;
        }
    }
}