Go backend development, learning open-source project source code together, focusing on simplicity and practicality.
This article explains how to reverse a singly‑linked list in groups of K nodes by locating each segment's head and tail, reversing the segment, and recursively processing the remainder, with a complete Go implementation and step‑by‑step reasoning.
This article explains the LeetCode 39 "Combination Sum" problem, illustrates recursion with an apple‑picking analogy, details the backtracking algorithm pattern, and provides a complete, well‑commented Go implementation that handles unlimited reuse of candidates and pruning based on the target sum.
This article explains how to solve LeetCode problem 162 (Find Peak Element) in O(log n) time using a binary‑search approach, detailing the three possible cases, providing pseudocode, and presenting a complete Go implementation that handles boundary conditions as negative infinity.
The article explains how to locate the left and right boundaries of the unsorted segment in LeetCode 581 by using two monotonic stacks that store indices, and provides a complete Go implementation that returns the length of the shortest subarray whose sorting makes the whole array ordered.
The article explains how to detect a cycle in a singly‑linked list using fast and slow pointers, then locate the cycle’s entry node by resetting the slow pointer to the head and moving both pointers one step at a time, with full Go implementation provided.
This article explains how to solve the classic “longest substring without repeating characters” problem using a sliding‑window technique, detailing pointer management, duplicate detection, and a complete Go implementation.
The article explains a dynamic‑programming approach to the classic “Maximum Subarray Sum” problem, defining dp[i] as the best sum ending at index i, deriving the recurrence dp[i]=max(dp[i‑1]+nums[i], nums[i]), initializing base cases, and providing complete Go code.
This article explains a recursive solution in Go for LeetCode problem 92, detailing how to reverse a sublist of a singly linked list between given positions by first locating the start node, using a helper to reverse the first n nodes, and correctly reconnecting the remaining parts.
The article explains how to determine whether a given push sequence and pop sequence form a valid stack operation by using a temporary Go slice as a stack, iterating through the push list, and repeatedly popping while the top matches the next pop element, finally returning a boolean result.
This article explains the Chain of Responsibility design pattern, illustrates it with a company expense‑approval scenario, and provides complete Go code—including an interface, Staff, Manager, and CEO structs—showing how to build a flexible, extensible approval chain.
