C++ auto produce sql_1

#include "pch.h"
#include <iostream>
#include "stdlib.h"
#include "time.h"
#include "string.h"
#define SIZE 7
#define DIM 21
//                         0, 1, 2  3  4  5  6
//					   	   A, B, C, D, E, F, ERD
char ERD[SIZE][SIZE] = { { 0, 1, 1, 0, 0, 0, 0 },//0
						 { 1, 0, 0, 1, 0, 1, 0 },//1
						 { 1, 0, 0, 1, 0, 0, 0 },//2
						 { 0, 1, 1, 0, 1, 1, 0 },//3
						 { 0, 0, 0, 1, 0, 0, 1 },//4
						 { 0, 1, 0, 1, 0, 0, 1 },//5
						 { 0, 0, 0, 0, 1, 1, 0 } };//6
/*                                    
0:1,2                                                                                     
1:0,3,5                                                            
2:0,3                                                               
3:1,2,4,5                                                                          
4:3,6                                                                                          
5:1,3,6                                      
6:4,5                                             
*/                                                             
char SEL[SIZE] = { 0, 0, 0, 0, 0, 0, 0 };
char FROM[SIZE];
char level[SIZE] = { 1, 0, 0, 0, 0, 0, 0 };
char ptr[SIZE] = { 0, 0, 0, 0, 0, 0, 0 };

bool cover()
{
	for (int i = 0; i < SIZE; i++) if (SEL[i] && level[i] == 0) return false;
	return true;
}

void span(int n)
{
	for (int j = 0; j < SIZE; j++)if (level[j] == 0)
	{
		int m = 0;
		for (int i = 0; i < SIZE; i++)if (ERD[i][j] && level[i] == n)
		{
			level[j] = n + 1;
			if (rand() % (++m) == 0) ptr[j] = i + 1;
		}
	}
}
int main()
{
	int a = 0, b = 0;
	srand(time(NULL)); rand();
	scanf("%d %d", &a, &b);
	SEL[a] = 1; SEL[b] = 1;

	for (int i = 0; i < 10; i++)
	{
		for (int i = 0; i < SIZE; i++) { FROM[i] = level[i] = ptr[i] = 0; FROM[i] = SEL[i]; }
		level[a] = 1;
		int n = 1;
		while (!cover()) span(n++);
		while (n-- > 1) 
			for (int i = 0; i < SIZE; i++) 
				if (level[i] == (n + 1) && FROM[i]) 
					FROM[ptr[i] - 1] = true;
		printf("FROM\t"); 
		for (int i = 0; i < SIZE; i++) 
			if (FROM[i])    
				printf("%d\t", i);  
		printf("\n");   
	}  
	return 0; 
}