Thread: Reading a file, my program misses out the first entry.

Hi there,

I am trying to read some data from a file, sort it and then write it into a new file. I cannot see where I am going wrong. The TESTfile.dat just contains integers from 1-10. When the program runs it misses off the 1 and adds an extra 10 at the end. Can anyone tell me where I am going wrong. My code is

Code:

#include<stdio.h>
#include<math.h>

int NDD[5]={0};
main()
{
  FILE *fp;
  int DD=0; //[10]={0};
  int i=0;
  if ((fp=fopen("/home/angela/Desktop/TESTfile.dat","r"))==NULL) printf("\nFile not opened\n");

  else printf ("File opened\n");
  
  const int bsz=100; char buf[bsz];
  while (fgets(buf, bsz, fp) != NULL ) {
    fscanf(fp,"%d",&DD);
    printf("DD= %d\n",DD);   
    int k;
    k=i-5*floor(i/5);
    NDD[k]+= DD;
    i++;
  }
  fclose(fp);

FILE *fout;
fout=fopen("sortedTESTFILE.dat","w");
int j;
for (j=0;j<5;j++) fprintf(fout,"%d\n",NDD[j]);
fclose(fout);

}

thanks.

You're using both fgets() and fscanf(). You can use either one, but you need to process the data from them, before they are overwritten with new data from the file.

So should I make DD an array i integers long, use a for loop over i and get rid of line 14 and 15?

And you need to work on your text layout too... don't put multiple statements on a line and indent according to some reasonable pattern.

Code:

  fp=fopen("/home/angela/Desktop/TESTfile.dat","r");
  if (fp ==NULL) 
    {  
       printf("\nFile not opened\n");
       exit(255);
     }
  else 
     printf ("File opened\n");
  
  const int bsz=100; 
  char buf[bsz];

See how much easier that is to follow?