Thread: Filling a structure

Hi. I have to create a genealogy list reading a file with the following input:

10/10/1983,Tom,Mark,Julia
...
...
11/02/1993,Tim,Sam,Jenny

I have X strings in the file, every string contains a date, the person name, then the name of the father and the name of the mother.

I'm creating a list of persons, reading the input file.

Code:

typedef struct {
  char date[MAX_PATH];
  char nameSurname[MAX_PATH];
  struct person * father;
  struct person * mother;
} person;

typedef struct list {
  person * aPerson;
  struct list * next;
} peopleList;

peopleList * head = NULL;

void addPerson(person * thePerson){
  peopleList * tmp = (peopleList *)malloc(sizeof(peopleList));
  tmp->aPerson = thePerson;
  tmp->next = head;
  head = tmp;
}

void createPerson(char * aDate, char * aName, char * aFather, char * aMother){
  person * tmp;
  tmp = (person *)malloc(sizeof(person));
  strcpy(tmp->date, aDate);
  strcpy(tmp->nameSurname, aName);
  // HERE I SHOULD GET THE POINTERS TO THE FATHER AND MOTHER (IF ANY.. NULL OTHERWISE)
  addPerson(tmp);
}

The problem is that when I want to create a person (while tokenizing the input) before inserting it, I have to look in the previously created person list If I already know the mother and the father of the person I'm creating and I don't know how to get the pointer to them that I will put in the person structure I'm creating.

Well if you only need to look at the previous entry, then after you add and set your pointer to next, set another pointer to the current entry. Then no matter what entry you're on, you still have a pointer to the entry before it. If you have to look at all the entries then you have to set your pointer back to the root and transverse through the list again searching for whatever you need.

this is a serach code to check wheather father and monther exsist in the list before. if so the pointer to that node return.

Code:

struct peoplelist * search(struct peoplelist *P, char father[], char mother [])
{
    while(P != NULL)
    {
        if((strcmp(P->father,father)==0) && (strcmp(P->mother,mother)==0))
        return p;
        
        P=P->next;
    }
    return NULL;
}

ssharish2005