Tries (Prefix trees)

A Trie (also called a prefix tree) is a tree-based data structure used to efficiently store and retrieve strings based on their prefixes. It can also be adapted for bitwise operations — for example, finding the maximum XOR of two numbers by building a binary trie over their bits.

Resources

• AOI 2026 Camp #1 | Lecture on Tries Part 1 - String Tries
• AOI 2026 Camp #1 | Lecture on Tries Part 2 - Binary Tries
• Strings — MIT OpenCourseWare
• GeeksforGeeks — Introduction to Trie Data Structure and Algorithm
• Codecademy — Complete Guide to Prefix Trees

AOI Camp Problemset

• Implement Trie (Prefix Tree)
• Map Sum Pairs
• Word Break
• Word Break II
• Short Encoding of Words
• Maximum XOR of Two Numbers in an Array
• Codeforces 282E