Binary tree

[felixb]

Hello,

I am writing a program that maintains basic information about people (each person have id num, first name, last name).
I keep all the data using a binary tree, which DATA is PERSON type that I created. the data is sorted by ID number of the person.

I want to develop a search in the binary tree by the name of the person (the tree sorted by ID, not by the name...)
What is the most efficient way to do it?

Thnks,

[GregBrannon]

What do you mean by "most efficient?" If you had a flat data structure, you knew what you meant by efficient, AND roughly how large the number of people it contained, you should be able to read up on the efficiency of the most popular sorting algorithms to find which you'd like to use. Since you're using a sorted binary tree, the data structure may already be optimized for a relatively simple (and efficient) search to find the desired record.

I suggest you read up on traversing a binary search tree (BST) to better understand the benefits of the data structure when looking for the data it contains.

You might also considering reordering the data by the item being searched, but that may only be practical for relatively small data sets.

[felixb]

The structure should support small and very large number of records.
The Tree already supports the search (quick and eddicient) records by key field, the ID Number of structure person).

What I'm asking is what is customary to do in cases where the tree has more data (in addition to key field - the id also has first and last name) and I want to do a quick search (and efficient) using this fields too?
How to perform this search?

[Norm]

It sounds like you want to have multiple keys to the records held in the collection/tree so the records can be accessed in different ways: by ID or by NAME or by ????

[felixb]

yes, the "DATA" of the tree is PERSON type (that i create) that have the following information about each person: ID, fname, lname, address.
the tree sorted by the ID
but also i want to search by fname for example

[Norm]

Can you create a separate index to the tree for each key you want to search on?

[felixb]

how to do it?

[Norm]

Are you asking how to build a tree with its contents sorted on another key?
You have the logic to build a tree sorted on ID, use that logic to build a tree sorted on NAME.

In other words build parallel trees with each tree having its own key.

[felixb]

my PERSON type have ID, fname, lname, address
and I built one tree that have that type.
you mean I should build 4 trees (1- ID, 2 - fname, 3 - lname, 4 - address) instead?
how will i do the link between the 4 trees?

[Norm]

how will i do the link between the 4 trees?

The trees are in parallel. Any changes made to one tree needs to be made to all of them to keep them in sync.

[felixb]

but if i have 3 persons for example:
id = 1, addr = z st
id = 2, addr = h st
id = 3, addr = a st

the id's tree will be like: (if i sort it by the id...)
2
1 3

the addr's tree wil be like: (if i sort it by the addr...)
h
a z

do you have some examples for source codes like this?

[Norm]

I don't have any sample code.

[felixb]

ok, but do you have an idea how can i link between the trees?

[Norm]

There is no link between the trees. Each one is separate from the other.
It is possible to add the same object to many different collections/trees. There shouldn't be anything in the object referring to the collection it is in.

[felixb]

Thank you!!!