Sudoku checker (Array Help)

[sugarless]

lately, care of my dad, i've been addicted to those sudoku puzzle's especially the super size ones.. i completed a C and a java course last year, so i figured hey i'm sure i can code something to help me with these puzzles! wrong...

i know there are simple to advanced little progs for this everywhere, but its an ego thing now.. basically i tackled the problem one way and got completely lost and wanted to jump out the window.. i want to start simple because i've forgotten a lot, especially file i/o..

aim:

basically i want to write a little console prog that will read a file eg. something called sudoku.in, where i can punch in the numbers (9rows, 9columns), either partially finished with 0's for spaces, or completed and either check if its valid, or return co-ordinates where its incorrect..

eg.

060104050
008305600
200000001
800406006
006000300
700901004
500000002
007206900
040508070

i figure i read the input of this file, into a 2dimensional array, and then check for duplicated numbers in rows or colums (ignoring 0's for spaces).. however, i completely forget 2d arrays and its driving me bonkers, because it seems embarassingly easy..

can anybody point me in the right direction.. or some useful code for file io, because the text book i have is completely useless, and the given example with the code gave me a compile error.....

[redhead]

Is this instruction of any help ? or perhaps the theory of 2d arrays or theory of matrixes
Else theres the old thread on 2D arrays.

For a quick reference, theres a well documented 2d array program written in Java.

[sugarless]

kind of.. now im a bit confused with the array/matrix differences, and how to check rows/columns.. and also start left corner as 1,1 not 0,0... i think my main problem is reading from a file into the array.. this is what i have so far;

#include "windows.h"
#include "stdio.h"
#include "stdlib.h"
#include "conio.h"

int main(int argc, char* argv[])

{
	int nSodukuArray[9][9];

	ZeroMemory(nSodukuArray,sizeof(nSodukuArray));

	char sLineBuf[256];

	FILE *f = fopen("soduku.in","rt");

	int row = 0, col = 0;

	while (fgets(sLineBuf,255,f))
	{
		for (col=0; col<9; col++)
		{
			nSodukuArray[row][col] = sLineBuf[col] - '0';
		}
		row++;
	}
	fclose(f);

	for (row = 0; row < 9; row++)
	{
		//...
	}

	for (col = 0; col < 9; col++)
	{
		//...
	}
	return 0;

}

[redhead]

If the file is presented as:

0123456789
1234567890
2345678901
3456789012
4567890123
5678901234
6789012345
7890123456
8901234567
9012345678

Then you should be able read it in with something like:

#include <stdio.h>

int main(){
    int nSodukuArray[9][9];
    FILE* fin;
    int i, j, ch;
    if(!(fin=fopen("soduku.in","r"))){
        printf("Error opening file\n");
        return -1;
    }
    for(i=0; i < 9 && !feof(fin); ++i){
        for(j=0; j < 9 && !feof(fin); ++j){
            nSodukuArray[i][j]=fgetc(fin);
            if(nSodukuArray[i][j] == '\n'){
                printf("Error reading from file\n");
                return -1;
            }
        }
        ch=fgetc(fin); /* discard '\n' on the line */
    }
    fclose(fin);
    /* do what ever with the 2d array */
    return 0;
}

Only problem here might be that you get your array mirrored since your columns now appears to be located as rows...
But when doing calculations and displaying that cen be rearranged.

[sugarless]

#include <fstream>
#include <stdio.h>

int main()
{
    /* sudoku array */
    int a[9][9];
    FILE* fin;
    int i, j, ch;
    if(!(fin=fopen("sudoku.in","r")))
    {
        printf("Error opening file\n");
        return -1;
    }
    /* input loop to read in sudoku array from sudoku.in */
    for(i=0; i < 9 && !feof(fin); ++i)
    {
        for(j=0; j < 9 && !feof(fin); ++j)
        {
            a[i][j] = fgetc( fin ) - '0';
            
            if(a[i][j] == '\n'){
                printf("Error reading from file\n");
                return -1;
        }
    }
        ch=fgetc(fin); /* discard '\n' on the line */
}    
    /* output loop to output the new 9x9 array */
    for (i=0; i < 9; ++i)
    {
        for (j=0; j < 9; ++j)
            printf("a[%d][%d]=%d ", i, j, a[i][j]);
    }
    fclose(fin);
}
return 0;
}

ok thanks! i finally tweaked it so the file io is right, it reads from the file into the array..

how would one go about scanning each row and each column in the array to see if numbers are repeated per row/column..?