Pointers and dinamic memory

[easyz]

Hello, I have to do some program, similiar to the Facebook.
I wrote the syntax, but it doesn't compile...I don't know what the problem is...
Will appreciate for any help!

http://www.turboupload.com/3i3jbpisaog5/Document.txt.html

[Incubbus]

post your code here in the code-brackets, please... nobody wants to wait 1 minute to download your code for a question that you asked for... in my opinion

[kbw]

Or deal with full screen popup adds.

[easyz]

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


typedef struct Person {
	int id;
	char* name;
	struct PersonList* friends;
} Person;

typedef struct PersonList {
	Person* person;
	struct PersonList* next;
} PersonList;


// list of all messages to use in your program
#define USER_NOT_EXIST "User does not exist\n"
#define ALREADY_FRIENDS "But users are already friends\n"
#define NOT_FRIENDS "But users are not friends\n"
#define USER_DETAILS "Name: %s, ID: %d, Friends: %d\n"
#define LIST_COMMON "List of common friends:\n"
#define NO_COMMON "No common friends\n"
#define MENU "Please choose an option:\n========================\n1. Add user\n2. Delete user\n3. Create friendship between two users\n4. Cancel friendship between two users\n5. Print all users sorted by popularity\n6. Print common friends\n0. Exit\n\nYour choice: "
#define ENTER_NAME "Enter the user's name [up to 100 chars]: "
#define ENTER_ID "Enter user ID: "
#define ENTER_FIRST_ID "Enter first user ID: "
#define ENTER_SECOND_ID "Enter second user ID: "
#define ENTER_ID_LIST_1 "Enter ID no. 1: "
#define ENTER_ID_LIST_X "Enter ID no. %d (0 to terminate): "

int PrintMenu();
// returns a new id to use for a person
int getNewId();

// returns a person* according to id, or NULL if user doesnt exist
Person* getPersonById(int id, PersonList* list);

// adds a person to list and returns the list
PersonList* addPerson(char* personName, PersonList* list);

// returns whether two people are friends
int areFriends(Person *first, Person* second);

// removes a person. Updates all relevant lists,
// returns the updated allPersons list.
PersonList* delPerson(int id, PersonList* allPersons);

// make persons id1, id2 to be friends
void makeFriends(int id1, int id2, PersonList* allPersons);

// initialize the program with the following information:
// persons: moshe, yoel, haim, ido, adam, ronen, gilad, dana, roni, michal, adi, omer
// friends: (note that friends are mutual)
// <Moshe,Yoel>, <Moshe,Ido>,<Moshe,Roni>,<Yoel,Ronen>,<Yoel,Omer>,<Yossi,Dana>,<Yossi,Adi>,<Gilad,Roni>,
// <Gilad,Adi>,<Dana,Michal>,<Adi,Omer>.
PersonList* initDatabase();

// cancel friendship of persons id1, id2
void cancelFriends(int id1, int id2, PersonList* allPersons);

// returns the number of friends of a person
int numOfFriends(Person* person);

// returns a sorted list of people by popularity and then lexicographically
PersonList *sortByPopularity(PersonList* allPersons);

// prints all people by popularity
void printPeopleByPopularity(PersonList* allPersons);

// prints common friends of persons,
// will also work if persons is a list of 1 person, in that case it will just print this person's friends.
void printCommonFriends(PersonList* persons);

void delFriend(Person *person,Person *buddy);

void addFriend (Person* person, PersonList* list);

int PrintMenu()
{
	int choise=10;
	do{
	printf("Please choose an option:\n");
	printf("========================\n");
	printf("1. Add user\n");
	printf("2. Delete user\n");
	printf("3. Create friendship between two users\n");
    printf("4. Cancel friendship between two users\n");
    printf("5. Print all users sorted by popularity\n");
    printf("6. Print common friends\n");
    printf("0. Exit\n\n");
    printf("Your choice:");
	scanf("%d",&choise);
	}
	while(choise>6 || choise<0);
	return choise;
}
// returns a new id to use for a person
int getNewId()
{
	static int id = 1;
	return id++;
}

// initialize the program with the following information:
// persons: moshe, yoel, haim, ido, adam, ronen, gilad, dana, roni, michal, adi, omer
// friends: (note that friends are mutual)
// <Moshe,Yoel>, <Moshe,Ido>,<Moshe,Roni>,<Yoel,Ronen>,<Yoel,Omer>,<Yossi,Dana>,<Yossi,Adi>,<Gilad,Roni>,
// <Gilad,Adi>,<Dana,Michal>,<Adi,Omer>.
PersonList* initDatabase() {
	PersonList *PList = NULL;
	PList = addPerson("Moshe", PList);
	PList = addPerson("Yoel", PList);
	PList = addPerson("Haim", PList);
	PList = addPerson("Ido", PList);
	PList = addPerson("Yossi", PList);
	PList = addPerson("Ronen", PList);
	PList = addPerson("Gilad", PList);
	PList = addPerson("Dana", PList);
	PList = addPerson("Roni", PList);
	PList = addPerson("Michal", PList);
	PList = addPerson("Adi", PList);
	PList = addPerson("Omer", PList);

	makeFriends(1,2, PList);
	makeFriends(1,4, PList);
	makeFriends(1,9, PList);
	makeFriends(2,6, PList);
	makeFriends(2,12, PList);
	makeFriends(5,8, PList);
	makeFriends(5,11, PList);
	makeFriends(7,9, PList);
	makeFriends(7,11, PList);
	makeFriends(8,10, PList);
	makeFriends(11,12, PList);

	return PList;
}

void main(){
	char User[100];
	int choise,id1,id2;
	PersonList *allPersons;
	allPersons=initDatabase();
	do
	{
	choise=PrintMenu();
	switch(choise)
	{
	case 1:
		printf("Enter the user's name [up to 100 chars]: ");
		gets(User);
		addPerson(User,allPersons);
		break;
	case 2:
		printf("Enter user ID: ");
		scanf("%d",&id1);
		if(getPersonById(id1,allPersons))
		{
			delPerson(id1,allPersons);
			break;
		}
	    else printf("User does not exist\n");
		break;
	case 3:
		printf("Enter first user ID: ");
        scanf("%d",&id1);
        printf("Enter second user ID: 2");
		scanf("%d",&id2);
		makeFriends(id1,id2,allPersons);
		break;
	case 4:
		printf("Enter first user ID: ");
        scanf("%d",&id1);
        printf("Enter second user ID: ");
		scanf("%d",&id2);
		cancelFriends(id1,id2,allPersons);
		break;
	case 5:
		printPeopleByPopularity(allPersons);
	    break;
	case 6:
		printCommonFriends(allPersons);
		break;
	}
	while(choise);
}

PersonList* addPerson(char* personName, PersonList* list){
	Person *newP;
	PersonList *newL;

	newP=(Person*)malloc( sizeof(Person) );
	newP->name=(char*)malloc( sizeof(char)*(strlen(personName)+1) );
	strcpy(newP->name,personName );
	newP->id=getNewId();
	newP->friends=NULL;
	
	newL=(PersonList*)malloc( sizeof(PersonList) );
	newL->person=newP;
	newL->next=list;

	return newL;
}

PersonList* delPerson(int id, PersonList* allPersons){
PersonList* tempL1,*tempL2,*tempF,*tempF1;


	for(tempL1=allPersons,tempL2=tempL1;tempL1!=NULL && id!=tempL1->person->id;tempL2=tempL1,tempL1=tempL1->next);

	if (tempL1==NULL)
		printf(USER_NOT_EXIST);

	for(tempF=tempL1->person->friends;tempF!=NULL;)
	{
		delFriend(tempF->person,tempL1->person);
		tempF1=tempF;		
		tempF=tempF->next;
		free(tempF1);
	}

	free(tempL1->person);
	
	if (tempL1==tempL2)
	{
		tempL1=tempL1->next;
		free(tempL2);
		return tempL1;
	}
	else
	{
		tempL2->next=tempL1->next;
		free(tempL1);
		return allPersons;
	}



}

void delFriend(Person *person,Person *buddy){
PersonList* tempL1,*tempL2;

	
	for(tempL1=person->friends,tempL2=tempL1; tempL1!=NULL && tempL1->person!=buddy;tempL2=tempL1,tempL1=tempL1->next);
	
	if(tempL1!=NULL)
	{
		if (tempL2!=tempL1)
		{
			tempL2->next=tempL1->next;
			free(tempL1);
		}
		else
		{
			person->friends=tempL1->next;
			free(tempL1);
		}

	}

}

Person* getPersonById(int id, PersonList* list)
{
	PersonList* tempL1;

	for(tempL1=list;tempL1!=NULL && id!=tempL1->person->id;tempL1=tempL1->next);
	if (tempL1==NULL)
		return NULL;
	else
	return tempL1->person;
}

[easyz]

void makeFriends(int id1, int id2, PersonList* allPersons)
{
	Person* person1,*person2;
	PersonList* list1,*list2;

	person1=getPersonById(id1, allPersons);
	person2=getPersonById(id2, allPersons);
	list1=(PersonList*)malloc( sizeof(PersonList) );
	list2=(PersonList*)malloc( sizeof(PersonList) );
	list1->person=person2;
	list2->person=person1;
	addFriend (person1, list1);
	addFriend (person2, list2);
}
void addFriend (Person* person, PersonList* list)
{
	PersonList* tempL1,*tempL2;

	for(tempL1=person->friends,tempL2=tempL1; tempL1!=NULL;tempL2=tempL1,tempL1=tempL1->next);
	if (tempL1==tempL2)
		person->friends=list;
	else
		tempL2->next=list;

}

int areFriends(Person *first, Person* second)
{
PersonList* list1,*list2;

for(list1=first->friends; list1!=NULL && list1->person!=second;list1->next);
if (list1==NULL)
	return 0;
for(list2=second->friends; list2!=NULL && list2->person!=first;list2->next);
if (list2==NULL)
	return 0;
return 1;

}

void cancelFriends(int id1, int id2, PersonList* allPersons)
{
	Person* person1,*person2;

	person1=getPersonById(id1, allPersons);
	person2=getPersonById(id1, allPersons);
	delFriend( person1, person2);
	delFriend( person2, person1);

}

int numOfFriends(Person* person)
{
	int i;
	PersonList* list1;

	for(i=0,list1=person->friends; list1!=NULL;i++, list1->next);

	return i;
}

PersonList *sortByPopularity(PersonList* allPersons)
{
	PersonList* list1,*list2,*list3;
	Person* tempP1;

	list3=NULL;
	while(list3!=allPersons)
	{
		list2=allPersons;
		if (list2->next!=NULL)
			list1=list2->next;
		else 
			return allPersons;

		while (list1!=list3)
		{
			if( strcpm(list1->person->name,list2->person->name)>0 )
			{
				tempP1=list1->person;
				list1->person=list2->person;
				list2->person=tempP1;
			}

			list2=list1;
			list1=list1->next;
		}
		if (list1==list3)
		{
			list3=list2;
		}

	}
}

Thanks in advance

[kbw]

If you correct the indentation in main, you'll see that the switch statement doesn't end correctly.

[easyz]

Thanks!!!
Now I have another problem:
The function "addFriend" makes me problems...
The debugger directs me to the "for" loop, there some problem with the values of tempL1 and tempL2
I don't understand what does this thing want!

[kbw]

person->friends=list;
Are you sure you want to do that? Aren't you supposed to be adding person to list and not the other way around?

Ave you considered using STL containers?

[Timtam]

This is stiil me, but from another username.
the problem is not in this line, but in the line of "for" declaration