| sets = [[i] for i in range(len(nums))] | |
| parent = [i for i in range(len(nums))] | |
| def union(a, b): | |
| set_a = parent[a] | |
| set_b = parent[b] | |
| if set_a == set_b: | |
| return |
Like redis cluster, we'll use a shard space of 2^14 = 16384. Essentially what this means is that we'll take our entire geo area, and split it into 16384 segments of approximately equal entries.
Each instance will be responsible for any number of segments, typically a cluster of segments that are geographically close.
| import array | |
| import collections | |
| import itertools | |
| # Placeholder constants | |
| FREE = -1 | |
| DUMMY = -2 | |
| class Dict(collections.MutableMapping): | |
| 'Space efficient dictionary with fast iteration and cheap resizes.' |
| Lisp interpreter in 90 lines of C++ | |
| I've enjoyed reading Peter Norvig's recent articles on Lisp. He implements a Scheme interpreter in 90 lines of Python in the first, and develops it further in the second. | |
| Just for fun I wondered if I could write one in C++. My goals would be | |
| 1. A Lisp interpreter that would complete Peter's Lis.py test cases correctly... | |
| 2. ...in no more than 90 lines of C++. | |
| Although I've been thinking about this for a few weeks, as I write this I have not written a line of the code. I'm pretty sure I will achieve 1, and 2 will be... a piece of cake! |
| package main | |
| import "sync" | |
| func primes() { | |
| var recur func(ch chan int) | |
| wg := sync.WaitGroup{} | |
| recur = func(ch chan int) { | |
| p := <-ch |
| package main | |
| import ( | |
| "time" | |
| "fmt" | |
| "context" | |
| "sync" | |
| ) | |
| func web() string { |
| """ | |
| Single Responsibility Principle | |
| “…You had one job” — Loki to Skurge in Thor: Ragnarok | |
| A class should have only one job. | |
| If a class has more than one responsibility, it becomes coupled. | |
| A change to one responsibility results to modification of the other responsibility. | |
| """ | |
| class Animal: | |
| def __init__(self, name: str): |
| <!DOCTYPE html> | |
| <html> | |
| <head> | |
| <meta charset="utf-8"> | |
| <meta name="viewport" content="width=device-width"> | |
| <title>JS Bin</title> | |
| </head> | |
| <body> |
| create table model( | |
| id serial primary key, | |
| name text, | |
| tags text[] | |
| ); | |
| insert into model(name, tags) values ('a', array['a', 'b', 'c']); | |
| insert into model(name, tags) values ('b', array['b', 'b', 'c']); | |
| select unnest(tags) as tag, count(*) from model group by tag; |
| def tushar(string, pattern): | |
| dp = [[False] * (len(pattern) + 1) for _ in range(len(string) + 1)] | |
| dp[0][0] = True | |
| for i in range(1, len(pattern)+1): | |
| if pattern[i-1] == "*": | |
| dp[0][i] = dp[0][i-2] | |
| for i in range(1, len(string)+1): | |
| for j in range(1, len(pattern)+1): |
