Reading comma seperated values from a file storing in a 1D and 2D array

问题

I have a code as below which would basically read a file with contents which look like Auckland,Hamilton,Rotorua,Wellington 0, 125, 235, 660
125, 0, 110, 535 235, 110, 0, 460 660, 535, 460, 0

Now what I want to do is I want to separate out the first line and store it in a character array and from second line till the end(which is the matrix basically) into a 2dimensional integer array and ofcourse splitting by commas. So far I have split file by commas and have stored into characters array but not able to get the number of elements from the array(i.e number of cities). Moreover I have just used fgets to read the first line. Is there any other efficient way to do this? Thank you.

 #include <stdio.h>
 #include <stdlib.h> 
 #include <string.h>
 #define MAXFLDS 200 
 #define MAXFLDSIZE 32
 void parse( char *record, char *delim, char arr[MAXFLDS][MAXFLDSIZE],int *fldcnt)
 {
char*p=strtok(record,delim);
int fld=0,fld1=0;
while(p)
{
    strcpy(arr[fld],p);
    fld++;
    p=strtok('\0',delim);
}   
*fldcnt=fld;
  }
  int main(int argc, char *argv[])
  {
char tmp[1024];
int fldcnt=0;
int j=0,k=0;
char arr[MAXFLDS][MAXFLDSIZE],arr1[MAXFLDS][MAXFLDSIZE];
int recordcnt=0;    
FILE *in=fopen("C:\\Users\\Sharan\\Desktop\\cities.txt","r"); 
if(in==NULL)
{
    perror("File open error");
    exit(EXIT_FAILURE);
}
fgets(tmp,sizeof(tmp),in);
parse(tmp,",",arr1,&fldcnt);
k=sizeof(arr1)/sizeof(arr1[0]);
printf("arr size:%d",k);
for(j=0;j<fldcnt;j++)
{
    printf("cities:%d\n",sizeof (arr1[j]));
}

while(fgets(tmp,sizeof(tmp),in)!=0)
{
    int i=0,j=0;
    recordcnt++;
    parse(tmp,", ",arr,&fldcnt);
    for(i=0;i<fldcnt;i++)
    {
        printf("%s\n",arr[i]);
    }
}
fclose(in);
return 0;   
  }

回答1:

The expression

sizeof (arr1[j])

returns the size of the actual array, i.e. MAXFLDSIZE, not the number of entries you put in it. You have to keep track of that yourself with variables.

来源：https://stackoverflow.com/questions/12505297/reading-comma-seperated-values-from-a-file-storing-in-a-1d-and-2d-array

标签

arrays

string

multidimensional-array

fopen