Thread: passing arrays into functions

hey guys so i have a program that works, but now I am trying to get function1() to work. What it has to do is bring in the array and populate it with random letters. I don't know much about functions, so I am kind of clueless about the errors that I am getting..

Code:

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

#define maxrow 20  //defines maxrow as a constant of 20
#define maxcol 30  //defines maxcol as a constant of 30

void function1(char array[][]);
void function4(int, int); //function to display the pairs count

int main( void )
{  // MARKS THE BEGINNING OF THE main( ) BLOCK OF STATEMENTS


int x = 0;
int y = 0;
int row = 0;
int col = 0;
int countX = 0;
int countY = 0;
srandom( (unsigned) time(NULL) );
char array[maxrow][maxcol];
char array[x][y];

/*
for (x=0;x<maxrow;x++)
    {
     for (y=0;y<maxcol;y++)
        {
         array[x][y] = random() % 26 + 'A';
         printf("%c ", array[x][y]);
        }
    printf("\n");
    }
printf("\n");
*/
function1(array[x][y]);


for (row=0;row<maxrow-1;row++)
    {
     for (col=0;col<maxcol; col++)
        {
         if (array[row][col] == array[row+1][col])
           {
            countX++;
           }
        }
    }

for(col=0;col<maxcol-1;col++)
    {
     for (row=0;row<maxrow;row++)
        {
         if (array[row][col] == array[row][col+1])
           {
            countY++;
           }
        }
    }


//calls function4 to display the countX and countY
function4 (countX, countY);


    return ( 0 ) ;

}   

char function1(array[x][y])
	{
int x = 0;
int y = 0;

	 for (x=0;x<maxrow;x++)
    {
     for (y=0;y<maxcol;y++)
        {
         array[x][y] = random() % 26 + 'A';
         printf("%c ", array[x][y]);
        }
    printf("\n");
    }
printf("\n");

return(array[x][y]);
	}


void function4(int countX, int countY)
    {
    printf("\nNumber of horizontal pairs: %d\n", countX);
    printf("\nNumber of vertical pairs: %d\n\n", countY);
     }

the errors when i compile:

Code:

test.c:8 error: array type has incomplete element type
test.c: In function 'main':
test.c:23: error: redeclaration of 'array' with no linkage
test.c.22: error: previous declaration of 'array' was here
test.c.37: error: type of formal parameter 1 is incomplete
test.c: At top level:
test.c:71 error: expected ')' before '[' token

Code:

void function1(char array[][]);

Only the left-most set of brackets can be empty in function parameters. That is the only dimension of the array that "decays to a pointer" when passed. The rest must have the correct number in the dimensions.

Code:

char array[maxrow][maxcol];
char array[x][y];

Two variables with the same name in the same scope is not allowed. Rename one.

Code:

char function1(array[x][y])

You need to provide a type for array. What is it an array of? int? char?