C - Can't print dynamic array values - c

Question

For school (yes, school projects) I need to adapt one C program...
I need to make an array with values from a txt file (that I think it was correctly done).
Now I wanted to print the values, and that's the problem! I tried many ways but I'm always seeing memory adress.
Here's the code:
int* init_dados(char *nome,int *m, int *n, int *iter)
{
FILE *f;
int *p, *q;
int i, j,k,contador=0,lixo=0,aux=0,flag=0;
f=fopen(nome, "r");
if(!f)
{
printf("Erro no acesso ao ficheiro dos dados\n");
exit(1);
}
fscanf(f, " %d %d", m,n);
p = malloc(sizeof(int)*(*m)*(*n));
if(!p)
{
printf("Erro na alocacao de memoria\n");
exit(1);
}
q=p;
for (i = 0; i < *m; i++)
{
for (j = 0; j<*n; j++)
{
//se ainda nao leu nada
if (flag == 0)
{
for (contador = 0; contador < *n; contador++)
{
fscanf(f, "%d", &lixo);
}
flag = 1;
break;
}
if (flag == 1)
{
fscanf(f, " %d", &k);
break;
}
for (contador = 0; contador < k; contador++)
{
fscanf(f, " %d", q++);
}
}
}
//PRINTING CODE
for (i = 0; i < *m; i++)
{
printf("\n");
for (j = 0; j < *n; j++)
{
printf("%d ", &q[j]);
q++;
}
}
fclose(f);
return p;
}
Waiting for your thoughts, thanks !
EDIT:
#iharob I've changed this:
for (contador = 0; contador < k; contador++)
{
fscanf(f, " %d", q++);
}
and
for (i = 0; i < *m; i++)
{
printf("\n");
for (j = 0; j < *n; j++)
{
printf("%d ", p[j]);
p++;
}
}
and still not working
EDIT2:
file:
10 10
1 1 1 1 1 1 1 1 1 1
2
1 8
2
5 6
4
1 2 3 4
1
1
4
1 2 5 8
2
6 10
1
9
4
1 2 3 5
1
8
1
7
print of the result so far:

Answer 1

This is wrong
printf("%d ", &q[i]);
change it to p[i] instead of &q[i]
printf("%d ", p[i]);
when you reach printf("%d ", q[i]) q points to the end of the array, so q[0] == q[lengthOfQ] that is past q, you assigned q = p; to keep p pointing to the begining of the array, hence you should use p in printf("%d ", q[i]); instead of q.
I think this code must be what you need
int *init_dados(char *nome,int *m, int *n, int *iter)
{
FILE *f;
int *p, *q;
int i, j, k, contador = 0, lixo = 0, flag = 0;
f = fopen(nome, "r");
if (f == NULL)
{
printf("Erro no acesso ao ficheiro dos dados\n");
exit(1);
}
fscanf(f, " %d %d", m, n);
p = malloc(sizeof(int) * *m * *n);
if (p == NULL)
{
fclose(f);
printf("Erro na alocacao de memoria\n");
exit(1);
}
q = p;
for (i = 0; i < *m; i++)
{
for (j = 0 ; j <* n ; j++)
{
//se ainda nao leu nada
if (flag == 0)
{
for (contador = 0 ; contador < *n ; contador++)
fscanf(f, "%d", &lixo);
printf("----\n");
flag = 1;
break;
}
else if (flag == 1)
{
fscanf(f, " %d", &k);
flag = 2;
break;
}
else if (flag == 2)
{
for (contador = 0 ; contador < k ; contador++)
fscanf(f, " %d", q++);
}
flag = 1;
}
}
}
//PRINTING CODE
for (i = 0; i < *m; i++)
{
for (j = 0; j < *n; j++)
printf("%d ", p[j]);
printf("\n");
}
fclose(f);
return p;
}

Answer 2

this code:
for (contador = 0; contador < k; contador++)
{
fscanf(f, " %d", q++);
}
will never be executed.
It is in a loop code block, where the driving force is 'flag' and flag is only set to 0 and 1, both the 0 case and the 1 case exit the overall 'for' loop.
Have you dumped the resulting 'p' array to assure the values are correct?
When running the program, did you notice that this code is never executed?

Answer 3

this code:
for (i = 0; i < *m; i++)
{
printf("\n");
for (j = 0; j < *n; j++)
{
printf("%d ", p[j]);
p++;
}
}
has the problem that 'p' should not be incremented.
for two reasons:
1) need to keep pointer to malloc'd memory
2) the variable 'j' is indexing off of 'p' so no need to increment 'p'

Answer 4

the following code compiles, but does raise a compiler warning about unused paramter
the code implements the OPs requirements
#include <stdio.h>
#include <stdlib.h>
// the 'iter' parameter is not used, raises compiler warning,
// suggest adding code to use it or remove that parameter
int* init_dados(char *nome,int *m, int *n, int *iter)
{
FILE *f = NULL;
int *p = NULL; // ptr to malloc'd memory
if( NULL == (p = malloc(1) ) )
{ // then, malloc failed
perror( "malloc failed" );
exit( EXIT_FAILURE );
}
// implied else, malloc successful
int *q = p; // steps into malloc'd memory
int j; // group loop index
int k; // group data size
int contador=0; // read loop counter
int lixo=0; // read and discard work area
if(NULL == (f=fopen(nome, "r") ) )
{ // then, fopen failed
perror("fopen failed" );
printf("Erro no acesso ao ficheiro dos dados\n");
exit( EXIT_FAILURE );
}
// implied else, fopen successful
if( 2 != (fscanf(f, " %d %d", m,n) ) )
{ // then, fscanf failed
perror( "fscanf failed for first line of file" );
free(p);
exit( EXIT_FAILURE );
}
// implied else, fscanf for m, n successful
//se ainda nao leu nada
for (contador = 0; contador < *n; contador++)
{
if( 1 != fscanf(f, " %d", &lixo) )
{ // then, fscanf failed for throwaway data
perror("fscanf failed for throwaway data line" );
free(p);
exit( EXIT_FAILURE );
}
// implied else, fscanf successful
} // end for
// for each data group
for (j = 0; j<(*n); j++)
{
if( 1 != fscanf(f, " %d", &k) )
{ // then, fscanf failed
perror( "fscanf failed for count of data in group" );
free(p);
exit( EXIT_FAILURE );
}
// implied else, fscanf successful
// input data from data group, with echo
printf("\nGroup Number: %d with data count: %d\n", j, k);
for (contador = 0; contador < k; contador++, q++)
{
if( 1 != fscanf(f, " %d", q) )
{ // then, fscanf failed
perror( "fscanf failed for data entry in data group" );
free(p);
exit( EXIT_FAILURE );
}
// implied else, fscanf successful
printf("%3d ", *q);
} // end for
} // end for
fclose(f);
return p;
} // end function: init_dados