pointers and structures in c [closed] - c

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I can't figure out how to access a certain parameter inside the structs that I am forced to use. The function gets a hotel and a passport number of one of the guests, and returns the number of the room in which the guest is staying, or NOT_FOUND if the guest is not at the hotel.
struct Guest
{
char name[20];
int passportNumber;
};
struct Room
{
int roomNumber;
int numOfGuests;
struct Guest* allGuests;//the Guests staying in the room
};
struct Hotel
{
int maxRooms;
int numOfUsedRooms;
struct Room** allRooms;
//array of Room* with physical size 'maxRooms'.
//only the first 'numOfUsedRooms' (logical size)
//rooms points to a room,all other pointers are
//NULL
};
int findGuestByPassportNumber(struct Hotel,int);
int main()
{
int i=0,j;
struct Hotel Cucamber;
printf ("before\n");//check
Cucamber.allRooms[i,i]->allGuests[i].name={"Spongebob"};
printf ("after\n");//check
Cucamber.allRooms[i,i]->allGuests[i].passportNumber=1234567890;
printf("%s",Cucamber.allRooms[i]->allGuests[i].name);
return 0;
}
The program doesn't even run because code blocks says:expected expression before '{' token.

Answer 1

First of all, you should google things like "c pointer" and so on and look at some basic tutorials.
Second, please think about your problem a bit first. You want to do a search. So if you search, you don't just know where it is, else you wouldn't have to search in the first place. So this means you'll have to check every available guest, wether his passport number matches the one your looking for.
This is obviously a case for "brute force"-search; so you'll have to do some loops. (Pseudocode):
Int Desiredpassportnumber = 1837748
Char *Name = NULL;
for( int i = 0; i < YourHotel.numberofRooms; i++){
for(int j = 0; j < YourHotel.allRooms[i].numofGuests; j++){
if(YourHotel.allRooms[i].allGuests[j].passportnum == desiredpassportnumber){
Name = YourHotel.allRooms[i].allGuests[j].name
break
}
}
}
If(name== NULL){
//handle No match found
}
Else {
//handle match found
}
This pseudocode, you'll have to add some semicolons and lowercaps some stuff etc. But this should be the idea behind it I think.
Hope this helps you in understanding your problem. :-)
To understand pointers better you should really just google a bit.