## What is prefix in trie?

A prefix tree is also known as a Trie; it is used to optimize the search complexities. If we search keys or words in a Binary Search Tree (BST) then the time complexity could go up to O (M * log N) whereas M is length of the words inserted and N is the total number of words inserted in the tree.

How does a trie represent each word in a set of words?

We know that tries are often used to represent words in an alphabet. Each trie has an empty root node, with links (or references) to other nodes — one for each possible alphabetic value. The shape and the structure of a trie is always a set of linked nodes, connecting back to an empty root node.

### Is trie a prefix tree?

In computer science, a trie, also called digital tree or prefix tree, is a type of search tree, a tree data structure used for locating specific keys from within a set.

How do you make the prefix trie?

To insert an element into a trie, we need to start from the root node and traverse the tree down, only creating nodes when they’re missing. When we’ve created all necessary nodes, we’ll set the boolean flag to true on the last one.

## What is the difference between tree and trie?

A tree is a general structure of recursive nodes. There are many types of trees. Popular ones are binary tree and balanced tree. A Trie is a kind of tree, known by many names including prefix tree, digital search tree, and retrieval tree (hence the name ‘trie’).

How would you optimize the space complexity in trie?

The implementation used in above post uses an array of alphabet size with every node. It can be made memory efficient. One way to implementing Trie is linked set of nodes, where each node contains an array of child pointers, one for each symbol in the alphabet.

### What is trie data structure explain with example?

For example, if we assume that all strings are formed from the letters ‘a’ to ‘z’ in the English alphabet, each trie node can have a maximum of 26 points. Trie is also known as the digital tree or prefix tree. The position of a node in the Trie determines the key with which that node is connected.

What is a trie good for?

Tries: Tries are an extremely special and useful data-structure that are based on the prefix of a string. They are used to represent the “Retrieval” of data and thus the name Trie. A Trie is a special data structure used to store strings that can be visualized like a graph.

## How do you optimize trie data structure?

One way to implementing Trie is linked set of nodes, where each node contains an array of child pointers, one for each symbol in the alphabet. This is not efficient in terms of time as we can’t quickly find a particular child. The efficient way is an implementation where we use hash map to store children of a node.

Is trie faster than hash table?

In my opinion a hash table does calculations on the string input, whereas a trie does address lookups on the string input. The address lookups might miss the cache, whereas calculations are done much faster I think as they don’t hit the cache.

### What is the use of trie data structure?

Trie is an efficient information reTrieval data structure. Using Trie, search complexities can be brought to optimal limit (key length). If we store keys in binary search tree, a well balanced BST will need time proportional to M * log N, where M is maximum string length and N is number of keys in tree.

How to represent nodes of the English alphabet in Trie?

A simple structure to represent nodes of the English alphabet can be as following, Inserting a key into Trie is a simple approach. Every character of the input key is inserted as an individual Trie node. Note that the children is an array of pointers (or references) to next level trie nodes.

## What is trie in C++?

208. Implement Trie (Prefix Tree) A trie (pronounced as “try”) or prefix tree is a tree data structure used to efficiently store and retrieve keys in a dataset of strings. There are various applications of this data structure, such as autocomplete and spellchecker.

What is the difference between a suffix tree and a trie?

Similar to the trie (but more memory efficient) is a suffix tree, or radix. In short, instead of storing single characters at every node, the end of a word, its suffix, is stored and the paths are created relatively. However, a radix is more complicated to implement than a trie.