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Coding Interview
Jason Yang · 05 Aug, 2026
The 18 coding interview patterns that cover almost every Blind 75 and NeetCode 150 problem, in Java — grouped, with when to reach for each and a deep dive on all of them.
Coding Interview
Jason Yang · 04 Aug, 2026
Advanced graphs in Java need named algorithms: Dijkstra for weighted shortest paths, Prim/Kruskal for a spanning tree, Bellman-Ford, and topological sort.
Coding Interview
Jason Yang · 04 Aug, 2026
Math and geometry problems in Java split two ways: manipulating a matrix in place with careful index arithmetic, and simulating arithmetic without overflow.
Coding Interview
Jason Yang · 04 Aug, 2026
Bit manipulation in Java rests on a few identities: XOR to cancel pairs, n & (n-1) to strip the lowest set bit, and shifts to add without a plus sign.
Coding Interview
Jason Yang · 04 Aug, 2026
2D DP in Java: when state needs two indices — two strings, a grid, or a mode — reading the recurrence from neighbor cells and rolling the table to O(n) space.
Coding Interview
Jason Yang · 04 Aug, 2026
A trie makes prefix a first-class query in Java: insert and startsWith in O(word length), wildcard matching, and a prefix tree that prunes a grid word search.
Coding Interview
Jason Yang · 04 Aug, 2026
Interval problems in Java almost all start by sorting, then one sweep: what to sort by, the overlap test, and counting concurrent intervals for room counts.
Coding Interview
Jason Yang · 04 Aug, 2026
Backtracking is a decision-tree DFS with an undo step. The choose/explore/unchoose template in Java, pruning dead branches, and the duplicate-skipping trick.
Coding Interview
Jason Yang · 04 Aug, 2026
Heap patterns in Java: the size-k trick for top-k, two heaps for a running median, and why a priority queue beats sorting when you only need the extreme.
Coding Interview
Jason Yang · 04 Aug, 2026
Stacks do two interview jobs in Java: matching what you must resolve later (parentheses, RPN), and the monotonic stack that finds next-greater in one O(n) pass.
Coding Interview
Jason Yang · 04 Aug, 2026
Linked list problems in Java are three pointer moves: the dummy head, fast and slow pointers, and in-place reversal — plus the one that's a data structure.
Coding Interview
Jason Yang · 03 Aug, 2026
Most graph interview problems are disguised — grids, prerequisites, connectivity. How to spot them, the visited set trees never needed, and BFS vs DFS in Java.
Coding Interview
Jason Yang · 03 Aug, 2026
Binary tree problems in Java are recursion plus the right traversal: pre/in/post-order DFS vs BFS, what each recursive call returns, and the BST in-order trick.
Coding Interview
Jason Yang · 03 Aug, 2026
Arrays and hashing in Java: how a hash set or map trades memory for O(1) lookups to turn O(n^2) scans linear, and when hashing is the wrong reflex.
Coding Interview
Jason Yang · 03 Aug, 2026
Greedy algorithms are quick to write and often wrong. How to tell when the greedy choice is provably optimal, the exchange argument, and the NeetCode problems.
Coding Interview
Jason Yang · 03 Aug, 2026
Dynamic programming in Java without the fear: how to name the state and find the recurrence, the 1D DP problem families, and when to memoize vs tabulate.
Coding Interview
Jason Yang · 03 Aug, 2026
Binary search in Java, beyond the sorted-array lookup: the boundary template that kills off-by-one bugs, searching on the answer, and rotated-array problems.
Coding Interview
Jason Yang · 03 Aug, 2026
The sliding-window pattern in Java: fixed vs variable windows, what to track inside, and how it solves Longest Substring and Minimum Window in one O(n) pass.
Coding Interview
Jason Yang · 27 Mar, 2026
The two-pointer pattern in Java: how converging pointers turn an O(n²) brute force into a single O(n) pass, and the decision rule that makes it safe.
Coding Interview
Jason Yang · 03 Dec, 2025
Divide and Conquer is more than Merge Sort: the 3-step design paradigm, how it differs from plain recursion, and the interview patterns that use it.
Coding Interview
Jason Yang · 02 Dec, 2025
Binary Search runs in O(log n) because it halves the search space every step. Here's the intuition, the math proof, and how it compares to linear search.
Coding Interview
Jason Yang · 01 Dec, 2025
Dynamic Programming demystified: at its core, DP is just Divide and Conquer plus memory. See the connection and it gets far easier to explain in interviews.
Coding Interview
Jason Yang · 28 Nov, 2025
Prefix Sum and Suffix Product explained: what these algorithm terms really mean, why they beat naive recomputation, and where they show up in problems.
Coding Interview
Jason Yang · 27 Nov, 2025
One-pass and greedy algorithms: how a single scan and greedy choices process large data with minimal memory — the core ideas and when they're optimal.
