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Tree Traversal

Oct 16, 2023C S
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More JavaScript Posts

LeetCode Product Except Self

Sep 13, 2023C S

0 likes • 11 views

/**
* @param {number[]} nums
* @return {number[]}
*/
var productExceptSelf = function(nums) {
var output = [];
var leftMult = 1;
var rightMult = 1;
for (var i=nums.length - 1; i >= 0; i--) {
output[i] = rightMult;
rightMult *= nums[i];
console.log({output: JSON.stringify(output), i})
}
for (var j=0; j < nums.length; j++) {
output[j] *= leftMult;
leftMult *= nums[j];
console.log({output: JSON.stringify(output), j})
}
return output;
};
console.log(productExceptSelf([1, 2, 3, 4]))

Flatten an array

Nov 19, 2022CodeCatch

0 likes • 3 views

const flat = arr => [].concat.apply([], arr.map(a => Array.isArray(a) ? flat(a) : a));
// Or
const flat = arr => arr.reduce((a, b) => Array.isArray(b) ? [...a, ...flat(b)] : [...a, b], []);
// Or
// See the browser compatibility at https://caniuse.com/#feat=array-flat
const flat = arr => arr.flat();
// Example
flat(['cat', ['lion', 'tiger']]); // ['cat', 'lion', 'tiger']

Mee6 Spam Calculator

Mar 10, 2022LeifMessinger

0 likes • 1 view

//Use at https://mee6.xyz/leaderboard/732262089447702588
//Higher the spammy stat, the more spammy that person is.
//This is because mee doesn't give experience to people who post more comments in a minute.
function statBlock(title, value){
let elm = document.createElement("div");
elm.className = "leaderboardPlayerStatBlock";
let titleElm = document.createElement("div");
titleElm.className = "leaderboardPlayerStatName";
titleElm.textContent = title;
let valueElm = document.createElement("div");
valueElm.className = "leaderboardPlayerStatValue";
valueElm.textContent = value;
elm.appendChild(titleElm);
elm.appendChild(valueElm);
elm.remove = function(){
this.parentElement.removeChild(this);
}
return elm;
}
for(let player of Array.from(document.getElementsByClassName("leaderboardPlayer"))){
if(player.spamminess) player.spamminess.remove();
let messages = null;
let experience = null;
const statBlockArray = Array.from(player.querySelectorAll(".leaderboardPlayerStatBlock"));
for(let statBlock of statBlockArray){
const statName = statBlock.querySelector(".leaderboardPlayerStatName").textContent;
const text = statBlock.querySelector(".leaderboardPlayerStatValue").textContent;
const number = ((text.includes("k"))? (text.replace("k","") * 1000.0) : +(text));
if(statName.includes("MESSAGES")){
messages = number;
}else if(statName.includes("EXPERIENCE")){
experience = number;
}
}
const stats = player.querySelector(".leaderboardPlayerStats");
const messagesElement = stats.firstChild;
const spamminess = ((messages/experience)*2000.0).toFixed(2);
player.spamminess = stats.insertBefore(statBlock("SPAMMINESS", spamminess), messagesElement);
}

Horizontal legend (d3.js)

Dec 17, 2024shaiRos

0 likes • 2 views

const rectSize = 15; // Size of the color box
const spacing = 5; // Space between legend items
let legend = canvas.append('g').attr('class','chart-legend')
.attr('transform', `translate(${0}, ${height + 3})`);
// Sample data for the legend
const legendData = [
{ label: 'low', color: '#1f77b4' },
{ label: 'medium', color: '#ff7f0e' },
{ label: 'high', color: '#2ca02c' },
{ label: 'very high', color: '#2ca02c' }
];
legend.selectAll('g')
.data(legendData)
.join('g')
.attr('class', 'legend-item')
.each(function (d, i) {
const legendItem = d3.select(this);
console.log(d.label)
console.log(d.label?.length)
let labelWidth = (d.label.length * 5) + 7 + 15
var bbox = legendItem.node().getBBox()
var width = bbox.width
console.log(width)
// Add rectangle for color
legendItem.append('rect')
.attr('width', rectSize)
.attr('height', rectSize)
.attr('fill', d.color);
// Add label
legendItem.append('text')
.attr('x', rectSize + spacing) // Position text to the right of the rectangle
.attr('y', rectSize / 2) // Align text vertically with the rectangle
.attr('dy', '.35em') // Adjust vertical alignment
.attr('text-anchor', 'start') // Align text to the start
.text(d.label)
.attr('fill', 'black'); // Optional: Text color
// legendItem.attr('transform', `translate(${i * (rectSize + spacing + labelWidth)}, 0)`) // Position each item horizontally
});
const legendItems_spacing = 12
var legendLength = 0
legend.selectAll('.legend-item').each(function(d,i) {
d3.select(this).attr('transform',function() {
var bbox = d3.select(this).node().getBBox()
var width = bbox.width
// if (width == 0) width = (d.text.length * 5) +15 // not in dom yet
let startingPosition = 0
if (i > 0) {
startingPosition = legendLength
}
legendLength += width + legendItems_spacing
// return `translate(${xx - (width + 30)},0$)`
return `translate(${startingPosition},0)`
})
})

doubly linked list

Nov 19, 2022CodeCatch

1 like • 0 views

class DoublyLinkedList {
constructor() {
this.nodes = [];
}
get size() {
return this.nodes.length;
}
get head() {
return this.size ? this.nodes[0] : null;
}
get tail() {
return this.size ? this.nodes[this.size - 1] : null;
}
insertAt(index, value) {
const previousNode = this.nodes[index - 1] || null;
const nextNode = this.nodes[index] || null;
const node = { value, next: nextNode, previous: previousNode };
if (previousNode) previousNode.next = node;
if (nextNode) nextNode.previous = node;
this.nodes.splice(index, 0, node);
}
insertFirst(value) {
this.insertAt(0, value);
}
insertLast(value) {
this.insertAt(this.size, value);
}
getAt(index) {
return this.nodes[index];
}
removeAt(index) {
const previousNode = this.nodes[index - 1] || null;
const nextNode = this.nodes[index + 1] || null;
if (previousNode) previousNode.next = nextNode;
if (nextNode) nextNode.previous = previousNode;
return this.nodes.splice(index, 1);
}
clear() {
this.nodes = [];
}
reverse() {
this.nodes = this.nodes.reduce((acc, { value }) => {
const nextNode = acc[0] || null;
const node = { value, next: nextNode, previous: null };
if (nextNode) nextNode.previous = node;
return [node, ...acc];
}, []);
}
*[Symbol.iterator]() {
yield* this.nodes;
}
}
const list = new DoublyLinkedList();
list.insertFirst(1);
list.insertFirst(2);
list.insertFirst(3);
list.insertLast(4);
list.insertAt(3, 5);
list.size; // 5
list.head.value; // 3
list.head.next.value; // 2
list.tail.value; // 4
list.tail.previous.value; // 5
[...list.map(e => e.value)]; // [3, 2, 1, 5, 4]
list.removeAt(1); // 2
list.getAt(1).value; // 1
list.head.next.value; // 1
[...list.map(e => e.value)]; // [3, 1, 5, 4]
list.reverse();
[...list.map(e => e.value)]; // [4, 5, 1, 3]
list.clear();
list.size; // 0

euclidean distance

Nov 19, 2022CodeCatch

0 likes • 3 views

const euclideanDistance = (a, b) =>
Math.hypot(...Object.keys(a).map(k => b[k] - a[k]));
euclideanDistance([1, 1], [2, 3]); // ~2.2361
euclideanDistance([1, 1, 1], [2, 3, 2]); // ~2.4495