How can I split an input using multiple delimiters? - c

Question

I want to split into tokens an lessons.txt file. This file has some people and these people's lessons. How can I do it ?
There is my lessons.txt file :
George Adam :Math,Science,Germany
Elizabeth McCurry :Music,Math,History
Tom Hans :Science,Music
Firstly, I want to split into ":". And I want to store names in an array. Secondly , I want to split into "," and these lessons I want to store an different array. How can I this ?
There is my code below :
char names[100] , *token, *lecture;
file=fopen("C:\\lessons.txt","r");
while(!feof(file))
{
fgets(names,sizeof(names),file);
printf("%s",names);
token=strtok(names,":");
while(token!=NULL)
{
token=strtok(NULL,":");
printf(" \n %s",token);
lecture=strtok(token,",");
while(lecture!=NULL)
{
lecture=strtok(NULL,",");
printf(" \n\n %s",lecture);
}
}
}
fclose(file);

Answer 1

So you want names to be stored in a separate array, and lessons to be stored in another?
You will need two separate tokens, you are using the same token for names and lessons.
Try this :
FILE *file;
file = fopen("C:\\lessons.txt", "r");
char names[100], *token, *difftok;
while (fgets(names, sizeof(names), file) != NULL) {
token = strtok(names, ":")
//puts(token); ---> George Adams
difftok = strtok(NULL, ",");
//puts(difftok); ---> Math
difftok = strtok(NULL, ",");
//puts(difftok); ---> Science
difftok = strtok(NULL, "\n");
//puts(difftok); ---> Germany
}
fclose(fp);
}
In my excerpt, token will always represent names, and difftok will always be lectures, from here I think you can figure out how to store the tokens into an array. Token goes into one, difftok into another.
Also, your EOF condition is wrong, feof returns a non-zero when it reaches end of file :
while(!feof(file))
Should be:
while(feof(file) == 0)
However, in this case I used fgets(...) != NULL because fgets return NULL when it reached end of file. You should probably use my condition as feof(file) == 0 encounters some end of file problems when used with your code and messes up the way the tokens parse the string.