Thread: Problem with reading a string matrix from a file

Good day C Gurs

I have a tring file called "Swap.txt" its content is the following matrix
char mat[ROW][COLS]=

"**.*.*....*",
"..*.*...**.",
"*...*.*....",
".*.*.*.*.*.",
"..*.*...*.*"


i want to convert it into a matrix in C for further manipulation and I used two codes for that

the first code is fine and give satisfactory results

Code:

Code:

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

#define ROWS 5
#define COLS 11
#define FILENAME "swap.txt"

int main() {
    char m[ROWS][COLS]; // should presumably be a char array
    int r, c;
    FILE *f;

    f = fopen(FILENAME, "r");
    if (f == NULL) {
        printf("Can't open %s.\n", FILENAME);
        exit(EXIT_FAILURE);
    }

    // read in the matrix
    for (r = 0; r < ROWS; r++)
        for (c = 0; c < COLS; c++)
            fscanf(f, " %c", &m[r][c]); // note the extra space

    // print out the matrix
    for (r = 0; r < ROWS; r++) {
        for (c = 0; c < COLS; c++)
            printf("%c", m[r][c]);
        printf("\n");
    }

    return 0;
}

The second code

Code:

Code:

f=fopen("filename","r");


 while(fgets(buf,row,f)!=NULL)
 {
     for(i=0;i<row;i++)
     {
         for(j=0;j<col;j++)
        {


  sscanf(buf,"%c", &mat[i][j])  ;


         }




        }


 }
for(i=0;i<row;i++)
     {
         for(j=0;j<col;j++)
        {


  printf("%c", mat[i][j])  ;


         }
printf("\n");


        }




 }

give me a matrix
...........
...........
...........
...........
...........


i see no stars here *
what is wrong with the second code?
Many thanks in advance

Originally Posted by Salem

> sscanf(buf,"%c", &mat[i][j]) ;
This doesn't walk through buf extracting each char in turn.
You just get multiple copies of buf[0]

Thanks a million Salem !