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>
#include <math.h>
#include <string.h>
#define LEN 4
#define SPACE 3

int main()
{
	int operands[LEN];
	char spaces[SPACE];
	char left[100];
	int index, sum;
	const char *operators[2] = {"+", "-"};
	scanf("%1d%1d%1d%1d", &operands[0], &operands[1], &operands[2], &operands[3]);

	for (int i = 0; i < pow(2, SPACE); i++) {
		sprintf(left, "%d", operands[0]);
		index = 0;
		sum = operands[0];
		for (int j = 0; j < SPACE; j++) {
			if ((i >> j) & 1) {
				sprintf(left, "%s%s%d", left, "+", operands[index+1]);
				sum += operands[index+1];
			} else {
				sprintf(left, "%s%s%d", left, "-", operands[index+1]);
				sum -= operands[index+1];
			}
			index++;
		}
		if (sum == 7) goto FINAL;
	}
	FINAL: printf("%s=7\n", left);
	return 0;
}