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Sequential Queue

Feb 6, 2021LeifMessinger
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graph example

Nov 19, 2022CodeCatch

0 likes • 4 views

class Graph {
constructor(directed = true) {
this.directed = directed;
this.nodes = [];
this.edges = new Map();
}
addNode(key, value = key) {
this.nodes.push({ key, value });
}
addEdge(a, b, weight) {
this.edges.set(JSON.stringify([a, b]), { a, b, weight });
if (!this.directed)
this.edges.set(JSON.stringify([b, a]), { a: b, b: a, weight });
}
removeNode(key) {
this.nodes = this.nodes.filter(n => n.key !== key);
[...this.edges.values()].forEach(({ a, b }) => {
if (a === key || b === key) this.edges.delete(JSON.stringify([a, b]));
});
}
removeEdge(a, b) {
this.edges.delete(JSON.stringify([a, b]));
if (!this.directed) this.edges.delete(JSON.stringify([b, a]));
}
findNode(key) {
return this.nodes.find(x => x.key === key);
}
hasEdge(a, b) {
return this.edges.has(JSON.stringify([a, b]));
}
setEdgeWeight(a, b, weight) {
this.edges.set(JSON.stringify([a, b]), { a, b, weight });
if (!this.directed)
this.edges.set(JSON.stringify([b, a]), { a: b, b: a, weight });
}
getEdgeWeight(a, b) {
return this.edges.get(JSON.stringify([a, b])).weight;
}
adjacent(key) {
return [...this.edges.values()].reduce((acc, { a, b }) => {
if (a === key) acc.push(b);
return acc;
}, []);
}
indegree(key) {
return [...this.edges.values()].reduce((acc, { a, b }) => {
if (b === key) acc++;
return acc;
}, 0);
}
outdegree(key) {
return [...this.edges.values()].reduce((acc, { a, b }) => {
if (a === key) acc++;
return acc;
}, 0);
}
}
const g = new Graph();
g.addNode('a');
g.addNode('b');
g.addNode('c');
g.addNode('d');
g.addEdge('a', 'c');
g.addEdge('b', 'c');
g.addEdge('c', 'b');
g.addEdge('d', 'a');
g.nodes.map(x => x.value); // ['a', 'b', 'c', 'd']
[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['a => c', 'b => c', 'c => b', 'd => a']
g.adjacent('c'); // ['b']
g.indegree('c'); // 2
g.outdegree('c'); // 1
g.hasEdge('d', 'a'); // true
g.hasEdge('a', 'd'); // false
g.removeEdge('c', 'b');
[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['a => c', 'b => c', 'd => a']
g.removeNode('c');
g.nodes.map(x => x.value); // ['a', 'b', 'd']
[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['d => a']
g.setEdgeWeight('d', 'a', 5);
g.getEdgeWeight('d', 'a'); // 5

LeetCode Contains Duplicate

Sep 13, 2023C S

0 likes • 2 views

/**
* @param {number[]} nums
* @return {boolean}
*/
var containsDuplicate = function(nums) {
return new Set(nums).size !== nums.length
};

List Largest Files Google Drive

Nov 16, 2023LeifMessinger

0 likes • 7 views

function filePath(file){
let folders = file.getParents();
const parents = [];
function makePathString(folderArray){
let path = "";
folderArray.forEach((folder)=>{
path += "/" + folder.getName();
});
return path;
}
while (folders.hasNext()) {
const folder = folders.next(); //This should hopefully remove that folder from the iterator
parents.unshift(folder);
}
return makePathString(parents);
}
function myFunction() {
const myEmail = Session.getEffectiveUser().getEmail();
Logger.log("My email is " + myEmail);
// Log the name of every file in the user's Drive.
var fileIterator = DriveApp.getFiles();
const files = []; //List of [File, size] entries
const filesMaxSize = 10;
while (fileIterator.hasNext()) {
var file = fileIterator.next();
const owner = file.getOwner();
//Only files I own
if((!(owner)) || (!(owner.getEmail)) || owner.getEmail() != myEmail){
continue;
}
const entry = [file, file.getSize()];
function slideUp(arr, index){
//Let's keep sliding it up so we don't have to sort it at the end.
for(let i = index; i > 0; --i){ //Stops at 1
const nextFile = arr[i-1];
if(nextFile[1] > entry[1]){
break;
}else{
//Swap with the next file to slide the file up
const temp = arr[i];
arr[i] = arr[i - 1];
arr[i - 1] = temp;
}
}
}
if(files.length < filesMaxSize){
files.push(entry);
slideUp(files, files.length - 1);
}else{
if(entry[1] > files[files.length - 1][1]){ //If it's bigger than the smallest file in the list.
files[files.length - 1] = entry; //Replace the smallest file
slideUp(files, files.length - 1); //Slide it up
}
}
}
for(let i = 0; i < filesMaxSize; ++i){
const file = files[i][0];
const size = files[i][1];
Logger.log(size + "\t" + filePath(file) + "/" + file.getName() + "\t" + file.getOwner().getName());
}
}

Simple Express Server

Oct 15, 2022CodeCatch

1 like • 264 views

const express = require('express')
const app = express()
const port = 3000
app.get('/', (req, res) => {
res.send('Hello World!')
})
app.listen(port, () => {
console.log(`Example app listening on port ${port}`)
})

arithmetic progression

Nov 19, 2022CodeCatch

0 likes • 2 views

const arithmeticProgression = (n, lim) =>
Array.from({ length: Math.ceil(lim / n) }, (_, i) => (i + 1) * n );
arithmeticProgression(5, 25); // [5, 10, 15, 20, 25]

linear search

Nov 19, 2022CodeCatch

0 likes • 3 views

const linearSearch = (arr, item) => {
for (const i in arr) {
if (arr[i] === item) return +i;
}
return -1;
};
linearSearch([2, 9, 9], 9); // 1
linearSearch([2, 9, 9], 7); // -1