Passing a 2-D Array To A Function

[18hRX9L8]

Hello, I recently wrote a program that uses recursion to fill an object.


EX.

*****

*   *

*   *

*****

To:

*****

*****

*****

*****

The problem is that when I try to pass the 2D-Array to the function that fills it, I get this error:
233 35 [Error] cannot convert 'char (*)[(((long long unsigned int)(((long long int)width) + -0x00000000000000001)) + 1)] {aka char (*)[(((long long unsigned int)(((long long int)width) + -0x00000000000000001)) + 1)]}' to 'char**' for argument '1' to 'char** fill(char**, int, int, int)'

So here is the code and the bolded part is where the problem is.

Some library code for those of you who want to try to compile it:

#include <cctype>
#ifndef _simpio_h
#define _simpio_h
#ifndef _genlib_h
#define _genlib_h
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <stdarg.h>
#include <stdbool.h>
#define FALSE false
#define TRUE true
#define ErrorExitStatus 1
typedef char *string;
typedef FILE *stream;
#define UNDEFINED ((void *) undefined_object)
extern char undefined_object[];
char undefined_object[] = "UNDEFINED";
void *GetBlock(size_t nbytes);
void *GetBlock(size_t nbytes)
{
     void *result;
     result = malloc(nbytes);
     //if (result == NULL) Error("No memory available");
     return result;
}
void FreeBlock(void *ptr);
void FreeBlock(void *ptr)
{
     free(ptr);
}
#define New(type) ((type) GetBlock(sizeof *((type) NULL)))
#define NewArray(n, type) ((type *) GetBlock((n) * sizeof (type)))
void Error(string msg, ...);
void Error(string msg, ...)
{
     va_list args;

     va_start(args,msg);
     fprintf(stderr, "Error: ");
     vfprintf(stderr, msg, args);
     fprintf(stderr, "\n");
     va_end(args);
     exit(ErrorExitStatus);
}
#define repeat for (;;)
#if defined( __BORLANDC__ )
#  if !defined ( __LARGE__ )
#    error The genlib.h library requires the LARGE memory model.
#  endif
#  if defined( _Windows )
#    define main void main
#  else
#    define main() void Main(void); \
            main() \
            { \
                Main(); \
                (void) getchar(); \
                return (0); \
            } \
            void Main(void)
#  endif
#endif
#endif
#define InitialBufferSize 120
string ReadLine(FILE *infile)
{
     string line, nline;
     int n, ch, size;

     n = 0;
     size = InitialBufferSize;
     line = (char *) GetBlock(size + 1);
     while ((ch = getc(infile)) != '\n' && ch != EOF)
     {
	  if (n == size)
          {
               size *= 2;
               nline = (string) GetBlock(size + 1);
               strncpy(nline,line,n);
               FreeBlock(line);
               line = nline;
          }
	  line[n++] = ch;
     }
     if (n == 0 && ch == EOF)
     {
          FreeBlock(line);
          return (NULL);
     }
     line[n] = '\0';
     nline = (string) GetBlock(n + 1);
     strcpy(nline , line);
     FreeBlock(line);
     return (nline);
}
string GetLine(void)
{
     return (ReadLine(stdin));	
}
int GetInteger(void)
{
     string line;
     int value;
     char termch;

     while (1)
     {
	  line = GetLine();
	  switch (sscanf(line, " %d %c", &value, &termch))
          {
	       case 1:
                  FreeBlock(line);
                  return value;
           case 2:
                  printf("Unexpected character: '%c'\n", termch);
                  break;
           default:
                  printf("Please enter an integer\n");
                  break;
          }
          FreeBlock(line);
          printf("Retry: ");
     }
}
long GetLong(void)
{
     string line;
     long value;
     char termch;

     while (1)
     {
	  line = (char *) GetLine();
	  switch (sscanf(line, " %ld %c", &value, &termch))
          {
	       case 1:
                  FreeBlock(line);
                  return value;
               case 2:
                  printf("Unexpected character: '%c'\n", termch);
                  break;
               default:
                  printf("Please enter an integer\n");
                  break;
          }
          FreeBlock(line);
          printf("Retry: ");
     }
}
double GetReal(void)
{
     string line;
     double value;
     char termch;

     while (1)
     {
	  line = GetLine();
	  switch (sscanf(line, " %lf %c", &value, &termch))
          {
	       case 1:
                  FreeBlock(line);
                  return value;
               case 2:
                  printf("Unexpected character: '%c'\n", termch);
                  break;
               default:
                  printf("Please enter an integer\n");
                  break;
          }
          FreeBlock(line);
          printf("Retry: ");
     }
}
#endif 

My Code:

char **fill(char **figure,int length,int width,int wplace)
{
	int counter;
	for(counter=0;counter<length;counter++)
	{
		if(!isspace(figure[counter][wplace]))
		{
			counter++;
			do
			{
				figure[counter][wplace]='*';
				counter++;
			}while(isspace(figure[counter][wplace]));
		}
	}
	if(wplace<width-1)
	{
		fill(figure,length,width,wplace+1);
	}
	else
	{
		return figure;
	}
}

int main(void)
{
	int counter,count,length,width;
	
	printf("This program fills objects.\n");
	printf("Enter the length of the object:  ");
	length=GetInteger();
	printf("Enter the width of the object:  ");
	width=GetInteger();
	
	char figure[length][width];
	char *row=new char[length];
	
	for(counter=0;counter<width;counter++)
	{
		if(counter>8)
		{
			printf("Row #%d: ",counter+1);
		}
		else
		{
			printf("Row #%d:  ",counter+1);
		}
		row=GetLine();
		for(count=0;count<length;count++)
		{
			figure[count][counter]=row[count];
		}
	}
	figure=fill(figure,length,width,0);
	
	printf("\n\n\nFilled object:\n\n");
	for(count=0;count<width;count++)
	{
		for(counter=0;counter<length;counter++)
		{
			printf("%c",figure[counter][count]);
		}
		printf("\n");
	}
	delete [] row;

getchar();
return(0);
}

(For those who cannot see it it is on line 55 in 'My Code'.)

I think the problem has to do with the fact that I have two variables defining the boundaries. Not sure... Any help would be nice.

[maeriden]

Does it still give you an error if you try changing line 36 to char** figure?

[vlad from moscow]

Array figure is declared as

char figure[length][width];

but in function fill the first parameter is declared as

char **figure

char [*][width] and char ** are two different types.

You can call function the following way

fill( (char **)figure,length,width,0);

And you shall not do the assignment

figure=fill(figure,length,width,0);

because as I said the array figure and the return type of the function have different types. You should write simply

fill( (char **)figure,length,width,0);

[18hRX9L8]

New problem , now the whole 2-D array is Nullified.

Problem with the types???

[vlad from moscow]

It means that function fill is invalid. Investigate its code.