jittdev

jittdev's Gists

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Categories: #ALGORITHMS | #Angular | #api | #Bootstrap5 | #C | #CRON | #DataGrip | #DataScience | #DOCKER | #error | #error_reporting | #git | #HTML | #Javascript | #Objective | #PostgreSQL | #Python | #REACT | #React | #REST | #RSpec | #Ruby | #shell | #SSL | #USEFUL | #VS | #VUE | #Wordpress | #XXXNoWork | #Uncategorized

ALGORITHMS (9)

• loading scripts asynchronously :: #ALGORITHMS

Tags: #ALGORITHMS

• [optimizing media attributes & specificity :: #ALGORITHM

jittdev

to speed up html page load

<script async> #as long as the script doesn't affect the DOM

<script defer> #waits as long as it takes for the html to load (third party script that aren't that important)

Critical Render Path loading: HTML -> CSS -> Javascript, and JS can pause finishing of html if not careful

//testing sites

jittdev

// if you only need media for certain screen sizes:

<link rel="stylesheet" href:"./style2.css" media="only screen and (min-width:500px)">

// so, at a minimum width of 500px, browser will load the style2.css

// and with CSS specificity can slow stuff down:

/* bad */
.header .nav .item .link a.important {

jittdev

<script type="text/javascript">
    const loadStyleSheet = src => {
        if(document.createStyleSheet) {
            document.createStyleSheet(src)
        }   else {
            const stylesheet = document.createElement('link');
            stylesheet.href = src;
            stylesheet.type = 'text/css';
            stylesheet.rel = 'stylesheet';
            document.getElementsByTagName('head')[0].appendChild(stylesheet)

jittdev

const array1 = ['a', 'c', 'g', 'x']
const array2 = ['z', 'y', 'a']

// Naive
function hasPairWithSum(arr, sum) {
    var len = arr.length;
    for(var i =0; i<len-1; i_++){
        for (var j = i+1; j<len; j++){
            if (arr[i] + arr[j] === sum)
                return true;

jittdev

find matching pair that equals a sum from a collection of numbers

[1,2,3,9]  Sum =8
[1,2,4,4]  Sum =8
how are these numbers given: memory/array?
repeating elements? can i repeat the same element? --same number might occur twice
are these integers or floats -- ints
can they be negative -- Yes
are they sorted? -- yes

jittdev

Sorting
Dynamic Programming
BFS + DFS (Searching)
Recursion

jittdev

Arrays
Stacks
Queues
Linked Lists
Trees
Tries
Graphs
Hash Tables

jittdev

1. Readable
2. Scalable Speed: Time Complexity = Big O
3. Scalable Memory: Space Complexity) = Big O

All three have trade-offs.

jittdev

// Rules:
//1: Worst Case
//2: Remove Constants
//3: Different terms for inputs
//4: Drop Non Dominant terms (n's) => 0(x^2+3x+100+x/2) becomes 0(x^2)

function doSomething(array1, array2) {
    array1.forEach(function(array1) {
        console.log(array1);
    })