Things I've learned writing them down.
Reading notes, post-mortems, and quick reference — written for the next time I need them.
claude-instructions
Enter plan mode for ANY non-trivial task (3+ steps or architectural decisions)
Best Time to Buy and Sell Stock
You are given an array prices where prices[i] is the price of a given stock on the ith day. You want to maximize your profit by choosing a single day to buy…
Check if the Array Is Sorted and Rotated
Given an array nums, return true if the array was originally sorted in non-decreasing order, then rotated some number of positions (including zero). Otherwis…
Max Consecutive Ones
Given a binary array nums, return the maximum number of consecutive 1's in the array.
Merge Sorted Array
You are given two integer arrays nums1 and nums2, sorted in non-decreasing order, and two integers m and n, representing the number of elements in nums1 and…
Pascal's Triangle
Given an integer numRows, return the first numRows of Pascal's triangle.
Two Sum & Three Sum
Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.
Find the Duplicate Number
Given an array of integers nums containing n + 1 integers where each integer is in the range [1, n] inclusive.
Majority Element I & II
Given an array nums of size n, return the majority element.
Merge Intervals
Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overlapping intervals that c…
Next Permutation
Find the next lexicographically greater permutation.
Rotate Image
You are given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise).
Set Matrix Zeroes
Given an m x n integer matrix matrix, if an element is 0, set its entire row and column to 0's.
Sort Colors
Given an array nums with n objects colored red, white, or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the ord…
Intersection of Two Linked Lists
Given the heads of two singly linked-lists headA and headB, return the node at which the two lists intersect. If the two linked lists have no intersection at…
Middle of the Linked List
Given the head of a singly linked list, return the middle node of the linked list.
Reverse Linked List
Given the head of a singly linked list, reverse the list, and return the reversed list.
Add Two Numbers
You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order, and each of their nodes contains a s…
Delete Node in a Linked List
There is a singly-linked list head and we want to delete a node node in it.
Merge Two Sorted Lists
this one is an easy on the leetcode however a hard on the striver and medium accoring to me due to doing it in contant space
prompt
I've added more files in this folder format for readability as a markdown file don't change how i have phrased my sentences they are written for me
creational-patterns
initialize once use always.
Scaling — Flash Reference
Ability of a system to handle increased load by adding resources without a full architectural overhaul.