Trying to initialize and fill a 2D char array with using structure - c

Question

What I am trying to do is use a structure to create and display a 2D array of characters in the function 'function1( )'. This array will be sent back to the main( ) so I can use it further in my program. However my program is plagued with problems. I am having trouble with pointers. I assume my problem is somewhere with either my pointers or my variables. I've tried several combinations with no effort. As a beginner, it probably is some odd combination that is not coming to my mind.
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define ROW 13
#define COL 16
typedef struct letter_array {
char** letters;
struct letter_array *ltr_ptr;
} larray;
void function1 (larray ** letter1[*][16]);
int function2 (larray letter2[][16]);
int function3 (larray letter3[][16]);
void function4 (int hor_ans, int ver_ans);
int main (void)
{
larray letter_list;
int vert, hori, **lptr;
lptr = malloc(ROW*sizeof(int*));
for(vert = 0; vert<ROW; vert++)
{
lptr [vert] = malloc(COL*sizeof(int));
}
printf("\n \t\t\t *** Hello! ***");
printf("\n This program will create a random selection of 180 upper-case"
" characters. \n\n");
function1(&letter_list); //Problem #1
printf("\n\nThank you for using my random character array program. \n"
"\t\t Have a good day! \n");
return ( 0 ) ;
}
void function1 (larray **letter1 [][16])
{
int i, z, funptr;
srandom((unsigned)time(NULL));
for(i=0; i<12; i++)
{
letter1 [i] <- (int*) funptr; // Problem #2-3
for(z=0; z<15; z++)
{
letter1[i][z] = random( )%26+'A'; // Problem #4
printf("%c ", letter1[i][z]);
}
printf("\n");
}
return ;
}
The errors are below and commented.
warning:passing argument 1 of 'function1' from incompatible pointer type
warning: cast to pointer from integer of different size
error: wrong type argument to unary minus
warning: assignment makes pointer from integer without a cast

Answer 1

I hope this helps.
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define ROW 13
#define COL 16
typedef struct letter_array {
char** letters;
struct letter_array *ltr_ptr;
} larray;
void function1 (larray * letter1); // here you just need a pointer to the structure
int function2 (larray letter2[][16]);
int function3 (larray letter3[][16]);
void function4 (int hor_ans, int ver_ans);
int main (void)
{
larray letter_list;
int vert, hori;
letter_list.letters = malloc(ROW*sizeof(int*)); // allocate memory to the char pointer in the structure
for(vert = 0; vert<ROW; vert++)
{
letter_list.letters[vert] = malloc(COL*sizeof(int)); // allocate the second 2D
}
printf("\n \t\t\t *** Hello! ***");
printf("\n This program will create a random selection of 180 upper-case"
" characters. \n\n");
function1(&letter_list); //Problem #1 pass a pointer to the structure
printf("\n\nThank you for using my random character array program. \n"
"\t\t Have a good day! \n");
return ( 0 ) ;
}
void function1 (larray *letter1) // just needs a pointer to the structure
{
int i, z;
srandom((unsigned)time(NULL));
for(i=0; i<ROW; i++) // used ROW
{
//letter1->letters[i] <- (int*) funptr; // Problem #2-3 this line not needed as near as i can tell
for(z=0; z<COL; z++) // used COL
{
letter1->letters[i][z] = random( )%26+'A'; // Problem #4 dereference pointer to member char **
printf("%c ", letter1->letters[i][z]);
}
printf("\n");
}
return ;
}