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: Wrong Answer)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void Standard_Input(int* a,int x)
{
    int i;
    for(i=3;i>=0;--i)
    {
        *(a+i)=x%10;
        x/=10;
    }
}

int main()
{
    char op1='0',op2='0',op3='0';
    int x,a[4];
    while(scanf("%d",&x)==1)
    {
        int i,flag=1;
        Standard_Input(a,x);
        for(i=0;i<4;++i)
        {
            if(a[i]>=10||a[i]<0)
            {
                flag=0;
                break;
            }
            else continue;
        }
        if(flag==1)
        {
            if(a[0]+a[1]+a[2]+a[3]==7)
            {
                op1=op2=op3='+';
                printf("%d%c%d%c%d%c%d=7\n",a[0],op1,a[1],op2,a[2],op3,a[3]);
            }
            else if(a[0]+a[1]+a[2]-a[3]==7)
            {
                op1=op2='+';
                op3='-';
                printf("%d%c%d%c%d%c%d=7\n",a[0],op1,a[1],op2,a[2],op3,a[3]);
            }
            else if(a[0]+a[1]-a[2]+a[3]==7)
            {
                op1=op3='+';op2='-';
                printf("%d%c%d%c%d%c%d=7\n",a[0],op1,a[1],op2,a[2],op3,a[3]);
            }
            else if(a[0]+a[1]-a[2]-a[3]==7)
            {
                op1='+';op2=op3='-';
                printf("%d%c%d%c%d%c%d=7\n",a[0],op1,a[1],op2,a[2],op3,a[3]);
            }
            else if(a[0]-a[1]+a[2]+a[3]==7)
            {
                op1='-';op2=op3='+';
                printf("%d%c%d%c%d%c%d=7\n",a[0],op1,a[1],op2,a[2],op3,a[3]);
            }
            else if(a[0]-a[1]+a[2]-a[3]==7)
            {
                op1=op3='+';op2='-';
                printf("%d%c%d%c%d%c%d=7\n",a[0],op1,a[1],op2,a[2],op3,a[3]);
            }
            else if(a[0]-a[1]-a[2]+a[3]==7)
            {
                op1=op2='-';op3='+';
                printf("%d%c%d%c%d%c%d=7\n",a[0],op1,a[1],op2,a[2],op3,a[3]);
            }
            else if(a[0]-a[1]-a[2]-a[3]==7)
            {
                op1=op2=op3='-';
                printf("%d%c%d%c%d%c%d=7\n",a[0],op1,a[1],op2,a[2],op3,a[3]);
            }
            else
            {
                printf("no answer!please input another one:");
                continue;
            }
        }
        else continue;
    }
    return 0;
}