From b66625f14906251259fb916b68816fc556c8c417 Mon Sep 17 00:00:00 2001
From: Marina S <138340846+bt3gl-google@users.noreply.github.com>
Date: Sun, 30 Jul 2023 21:48:33 -0700
Subject: [PATCH] Update README.md
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## tries
+
+
+
+* tries, also called prefix tree, are a variant of n-ary tree in which characters are stored in each node.
+* each trie node represents a string (a prefix) and each path down the tree represents a word. note that not all the strings represented by trie nodes are meaningful.
+* the root is associated with the empty string.
+* the * nodes (null nodes) are often used to indicate complete words (usually represented by a special type of child) or a boolean flag that terminates the parent node.
+* a node can have anywhere from 1 through alphabet_size + 1 child.
+* can be used to store the entire english language for quick prefix lookup (O(k), where k is the length of the string). they are also widely used on autocompletes, spell checkers, etc.
+* tries structures can be represented by arrays and maps or trees.
+
+
+
+### insertion
+
+
+
+* similar to a bst, when we insert a value to a trie, we need to decide which path to go depending on the target value we insert.
+* the root node needs to be initialized before you insert strings.
+
+
+
+### search
+
+
+
+* all the descendants of a node have a common prefix of the string associated with that node, so it should be easy to search if there are any words in the trie that starts with the given prefix.
+* we go down the tree depending on the given prefix, once we cannot find the child node, the search fails.
+* we can also search for a specific word rather than a prefix, treating this word as a prefix and searching in the same way as above.
+* if the search succeeds, we need to check if the target word is only a prefix of words in the trie or if it's exactly a word (for example, by adding a boolean flag).
+
+