Reading Data

[code_lover]

Hi all, I am a beginner in C , I need help in reading data from a standard input and storing it in array .I need to read sudoku data's in a file name sudoku.txt and store the values in an array.

[laserlight]

What have you tried?

[quzah]

Look up fscanf, fgets, or some of the f-ing functions. RTFM.


Quzah.

[code_lover]

this is what I have come up with ...

int c;
File *data;
data=open("sudoku.txt","r");
c=getc(data);

[quzah]

Ok, so that gets you one character. Go read about arrays, and see if you can put those in an array. (Also, read about loops.)


Quzah.

[code_lover]

How will the compiler know the path of the file??

data=fopen("sudoku.txt","r");

[quzah]

You specify it. Otherwise it defaults to where your executable is. You could always RTFM (click that) like I said in my first post.

DESCRIPTION
The fopen() function opens the file whose name is the string pointed to
by path and associates a stream with it.

If you want to be a programmer, you need to learn to look things up.


Quzah.

[CommonTater]

How will the compiler know the path of the file??

data=fopen("sudoku.txt","r");

No... you have to tell it a fully qualified path to the file... What you have only works if the file is in the current working directory.

[code_lover]

Is working now!

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

int main()
{
 int c,grid[9][9];
 int i=0,j=0;
 FILE *data;
 data=fopen("sudoku1.txt" ,"r");
 
 while ( fscanf(data, "%d", &c) == 1 ) {
 		if(c==' ')
		{
		 continue;
		} 
		else if(c=='\n')
		{
		 i=0;
		 j++;
		}       
        grid[i][j]=c;
		printf("%d\n",grid[i][j++]);
		counter++;
return 0;
}

[CommonTater]

Well, except you should turn the warnings up on your compiler and pay attention to it's reports...
I'm betting it's complaining about an implicit declaration of counter ...

Also there are still logic problems in your code... You really need to print that out the grid values to make sure it's capturing the data correctly...

		printf("grid[%d][%d] = %d\n",i,j,grid[i][j++]);

'Cause I'm betting you're running way off the end of your grid on the j axis.


First and most important lesson in programming... "Compiles" does not mean "Works".