// leetcode patterns
Algorithm Patterns,
One Session at a Time
16 tutoring sessions distilled into interview-ready notes — from the binary-search template that never off-by-ones to DP, graphs, and probability. Every classic Leetcode problem, solved in Java with the pattern spelled out.
01
Leetcode · Session 1
Binary Search & Binary Reduction
One loop template that never goes out of bounds — first/last occurrence, rotated arrays, 2D matrices, and binary search on the answer space.
Jul 03, 2026↗
02
Leetcode · Session 2
Sorting Algorithms
Quicksort, mergesort, heapsort and counting sort — when each wins, their invariants, and the sorting-based patterns interviewers love.
Jul 03, 2026↗
03
Leetcode · Session 3
Linked List, Queue & Stack
Dummy heads, fast/slow pointers, in-place reversal, and cycle detection — the pointer patterns that trip candidates up.
Jul 03, 2026↗
04
Leetcode · Session 4
Stack & Queue in Java
Monotonic stacks, deque tricks, and the queue/stack patterns behind next-greater-element, sliding windows, and expression parsing.
Jul 03, 2026↗
05
Leetcode · Session 5
Binary Tree, BST & Divide and Conquer
Traversal orders, BST invariants, and the divide-and-conquer recursion that solves most tree interview questions.
Jul 03, 2026↗
06
Leetcode · Session 6
Heap, HashMap & Graph
Priority queues, hash-based lookups, and graph traversal (BFS/DFS/Dijkstra) — the workhorse structures behind hard problems.
Jul 03, 2026↗